Method for reporting power headroom and corresponding user equipment

ABSTRACT

The present disclosure relates to a communication method and system for converging a 5 th -Generation (5G) communication system for supporting higher data rates beyond a 4 th -Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services.

TECHNICAL FIELD

The present application relates to the technical field of mobilecommunications, and in particular to a method for reporting powerheadroom and a corresponding user equipment.

BACKGROUND ART

To meet the demand for wireless data traffic having increased sincedeployment of 4G communication systems, efforts have been made todevelop an improved 5G or pre-5G communication system. Therefore, the 5Gor pre-5G communication system is also called a ‘Beyond 4G Network’ or a‘Post LTE System’. The 5G communication system is considered to beimplemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, soas to accomplish higher data rates. To decrease propagation loss of theradio waves and increase the transmission distance, the beamforming,massive multiple-input multiple-output (MIMO), Full Dimensional MIMO(FD-MIMO), array antenna, an analog beam forming, large scale antennatechniques are discussed in 5G communication systems. In addition, in 5Gcommunication systems, development for system network improvement isunder way based on advanced small cells, cloud Radio Access Networks(RANs), ultra-dense networks, device-to-device (D2D) communication,wireless backhaul, moving network, cooperative communication,Coordinated Multi-Points (CoMP), reception-end interference cancellationand the like. In the 5G system, Hybrid FSK and QAM Modulation (FQAM) andsliding window superposition coding (SWSC) as an advanced codingmodulation (ACM), and filter bank multi carrier (FBMC), non-orthogonalmultiple access (NOMA), and sparse code multiple access (SCMA) as anadvanced access technology have been developed.

The Internet, which is a human centered connectivity network wherehumans generate and consume information, is now evolving to the Internetof Things (IoT) where distributed entities, such as things, exchange andprocess information without human intervention. The Internet ofEverything (IoE), which is a combination of the IoT technology and theBig Data processing technology through connection with a cloud server,has emerged. As technology elements, such as “sensing technology”,“wired/wireless communication and network infrastructure”, “serviceinterface technology”, and “Security technology” have been demanded forIoT implementation, a sensor network, a Machine-to-Machine (M2M)communication, Machine Type Communication (MTC), and so forth have beenrecently researched. Such an IoT environment may provide intelligentInternet technology services that create a new value to human life bycollecting and analyzing data generated among connected things. IoT maybe applied to a variety of fields including smart home, smart building,smart city, smart car or connected cars, smart grid, health care, smartappliances and advanced medical services through convergence andcombination between existing Information Technology (IT) and variousindustrial applications.

In line with this, various attempts have been made to apply 5Gcommunication systems to IoT networks. For example, technologies such asa sensor network, Machine Type Communication (MTC), andMachine-to-Machine (M2M) communication may be implemented bybeamforming, MIMO, and array antennas. Application of a cloud RadioAccess Network (RAN) as the above-described Big Data processingtechnology may also be considered to be as an example of convergencebetween the 5G technology and the IoT technology.

DISCLOSURE OF INVENTION Technical Problem

With respect to a Licensed Assisted Access (LAA) system, it is urgent toprovide a novel power adjustment method and PHR calculation and reportmethod.

Solution to Problem

To overcome the technical problems or at least partially solve thetechnical problems, the following technical solutions are proposed.

An embodiment of the present invention provides a power allocationmethod, comprising the following steps of:

by a user equipment (UE), receiving uplink scheduling information, anddetermining a corresponding uplink transmit power on each uplink carrieraccording to the uplink scheduling information; and

according to an actual maximum uplink transmit power in a firstreference subframe of the UE and a predefined first priority, adjustingthe determined uplink transmit power of each uplink carrier, and/ordetermining whether to transmit an uplink signal, the first referencesubframe being a subframe which is determined according to the uplinkscheduling information to transmit an uplink channel/signal.

An embodiment of the present invention provides a method for reportingpower headroom, comprising the following steps of:

when conditions for reporting a Power Headroom Report (PHR) aresatisfied, by a user equipment, selecting, from at least one uplinkcarrier, one uplink carrier for reporting the PHR, and determining anuplink subframe probably used to transmit PHR, the uplink subframe beinga first reference subframe;

according to uplink scheduling information received in or before asecond reference subframe, determining PHR contents of each uplinkcarrier to be reported in the first reference subframe, and determininga PHR value according to the PHR contents; and

generating a PHR of each corresponding uplink carrier according to thedetermined PHR value of each uplink carrier, and reporting the generatedPHR of each uplink carrier on the selected uplink carrier and theselected subframe.

Preferably, the second reference subframe is not prior to a subframesatisfying PHR trigger conditions, and the second reference subframe isbefore the first reference subframe; and, a time interval between thesecond reference subframe and the first reference subframe is not lessthan a minimum processing time required by the UE to generate the PHR.

Preferably, the second reference subframe is a subframe at a point intime when a Media Access Control (MAC) layer starts generating a PHR MACcontrol element; and/or, the second reference subframe is a subframe ata point in time when an MAC layer starts generating an MAC Protocol DataUnit (MAC PDU) packet containing a PHR MAC control element.

Preferably, if the PHR is reported on the uplink carrier by two-stepscheduling, the first reference subframe probably used to transmit PHRis a subframe which is determined by a fixed offset with respect to thetime of receiving a first scheduling signaling.

Preferably, if the PHR is reported on the uplink carrier by two-stepscheduling, the first reference subframe probably used to transmit PHRis a subframe transmitting the PHR.

Preferably, the step of determining PHR contents of each uplink carrierto be reported in the first reference subframe comprises:

determining the PHR type of each corresponding uplink carrier, the PHRtype comprising a real PHR or a virtual PHR;

wherein, the step of determining a PHR value according to the PHRcontents, comprises:

calculating a PHR value according to the determined PHR type and/or apredefined time unit.

Preferably, the step of determining the PHR type of each correspondinguplink carrier comprises at least one of the following ways:

for an uplink carrier, the PHR type of the uplink carrier is a real PHR,if in the second reference subframe, it has been already determined thatan uplink channel/signal on this uplink carrier is to be transmitted inthe first reference subframe; for an uplink carrier, the PHR type of theuplink carrier is a virtual PHR, if in the second reference subframe, ithas not been determined yet that an uplink channel/signal on this uplinkcarrier is to be transmitted in the first reference subframe; and

for an uplink carrier, the PHR type of the uplink carrier is a virtualPHR, if in the second reference subframe, it has already been determinedthat an uplink channel/signal on this uplink carrier is not to betransmitted in the first reference subframe.

Preferably, the step of determining the PHR type of each correspondinguplink carrier comprises at least one of the following:

for an uplink carrier, the PHR type of the uplink carrier is a real PHR,if in the second reference subframe, it has already been determined thatthe uplink scheduling corresponding to the first reference subframe isone-step scheduling and the scheduling information indicates the uplinktransmission in the first reference subframe; or otherwise, the PHR typeof the uplink carrier is a virtual PHR.

Preferably, the step of determining the PHR type of each correspondinguplink carrier further comprises:

for an uplink carrier scheduled by the two-step scheduling, the PHR typeof the uplink carrier is a virtual PHR, if the first schedulingsignaling has been received in or before the second reference subframe,but the second scheduling signaling has not been received.

Preferably, the step of determining the PHR type of each correspondinguplink carrier comprises at least one of the following:

for an uplink carrier, the PHR type of the uplink carrier is a real PHR,if in the second reference subframe, it has already been determined thatan uplink channel/signal on this uplink carrier is to be transmitted inthe first reference subframe;

for an uplink carrier, the PHR type of the uplink carrier is a virtualPHR, if in the second reference subframe, it has already been determinedthat an uplink channel/signal on this uplink carrier is not to betransmitted in the first reference subframe; and

for an uplink carrier, the PHR type of the uplink carrier is a real PHR,if in the second reference subframe, it has already been determined thatan uplink channel/signal on this uplink carrier is to be transmitted inthe first reference subframe or for an uplink channel/signal is possiblyto be transmitted in the first reference subframe.

Preferably, the step of determining the PHR type of each correspondinguplink carrier comprises at least one of the following situations:

for an uplink carrier by one-step scheduling, the PHR type of the uplinkcarrier is a virtual PHR, if in or before the second reference subframe,uplink scheduling information which schedules the uplink transmission tobe transmitted on the uplink carrier in the first reference subframe isnot received or the received uplink scheduling information indicates theuplink transmission in a subframe other than the first referencesubframe; and, if the uplink scheduling information has been received inor before the second reference subframe, and the uplink schedulinginformation which schedules the uplink transmission to be transmitted onthe uplink carrier in the first reference subframe, the PHR type of theuplink carrier is a real PHR; and

for an uplink carrier by two-step scheduling, the PHR type of the uplinkcarrier is a virtual PHR, if in or before the second reference subframe,a second scheduling signaling has been received, and the subframe totransmit the uplink transmission on the uplink carrier triggered by thesecond scheduling signaling is not the first reference subframe; and, ifa second scheduling signaling has been received in or before the secondreference subframe, and the subframe to transmit the uplink transmissionon the uplink carrier triggered by the second scheduling signaling isthe first reference subframe, the PHR type of the uplink carrier is areal PHR.

Preferably, for an uplink carrier scheduled by the two-step scheduling,if in or before the second reference subframe, a first schedulingsignaling has been received, but a second scheduling signaling has notbeen received, the step of determining the PHR type of eachcorresponding uplink carrier comprises at least one of the followingsituations:

if the first scheduling signaling indicates the an uplink channel/signalto be transmitted in a subframe other than the first reference subframe,the PHR type of the uplink carrier is a virtual PHR;

if the first reference subframe has been out of a valid time window ofthe first scheduling signaling, the PHR type of the uplink carrier is avirtual PHR;

if the time interval between the first reference subframe and thesubframe in which the first scheduling signaling is received is lessthan a predefined threshold X, the PHR type of the uplink carrier is avirtual PHR;

if the possibility of transmitting an uplink channel/signal in the firstreference subframe cannot be excluded by the first scheduling signaling,the PHR type of the uplink carrier is a real PHR; and

if the first scheduling signaling has not been received in or before thesecond reference subframe, the PHR type of the uplink carrier is avirtual PHR.

Preferably, for an uplink carrier scheduled by the two-step scheduling,if a first scheduling signaling has been received in or before thesecond reference subframe, the step of determining the PHR type of eachcorresponding uplink carrier comprises at least one of the followingsituations:

if the first scheduling signaling indicates an uplink channel/signal tobe transmitted in a subframe other than the first reference subframe,the PHR type of the uplink carrier is a virtual PHR;

if the first reference subframe is out of a valid time window of thefirst scheduling signaling, the PHR type of the uplink carrier is avirtual PHR;

if the time interval between the first reference subframe and thesubframe in which the first scheduling signaling is received is lessthan a predefined threshold X, the PHR type of the uplink carrier is avirtual PHR;

if the possibility of transmitting an uplink channel/signal in the firstreference subframe cannot be excluded by the first scheduling signaling,the PHR type of the uplink carrier is a real PHR.

Preferably, the step of determining the PHR type of each correspondinguplink carrier comprises:

if both a signaling for two-step scheduling and a signaling for one-stepscheduling has been received in or before the second reference subframe,and if the signaling for one-step scheduling schedules the uplinktransmission of a first subframe, calculating a real PHR according tothe one-step scheduling signaling; if the signaling for one-stepscheduling does not schedule the uplink transmission of the first uplinksubframe but the UE has received a first scheduling signaling fortwo-step scheduling, and the first reference subframe is within a validtime window of the first scheduling signaling, calculating, by the UE, areal PHR according to the first scheduling signaling; and/or,

if a multiple of first scheduling signalings have been received in orbefore the second reference subframe, and the second schedulingsignalings corresponding to the first scheduling signalings have beennot received, then, within the valid time window of the first schedulingsignalings, the PHR type of the corresponding uplink carrier is a realPHR. Furthermore, the UE selects, according to a predefined rule, one ofthe first scheduling signalings and then determine the PHR type is areal PHR,

-   -   selecting the first received first scheduling signalings as a        reference, and calculating a real PHR, or,    -   selecting the last received first scheduling signalings as a        reference, and calculating a real PHR, or,    -   if all the first scheduling signalings are received in a same        subframe, selecting a first scheduling signaling with a lowest        PDCCH/EPDCCH search space index number as a reference, and        calculating a real PHR.

Preferably, the step of calculating a PHR value according to thedetermined PHR type and/or a predefined time unit comprises:

when it is selected to transmit PHRs on an uplink carrier with a longerTransmission Time Interval (TTI) length, the PHR of other uplinkcarriers with relatively shorter TTI length is calculated based on thefirst shorter TTI within the first reference subframe.

Preferably, the step of calculating a PHR value according to thedetermined PHR type and/or a predefined time unit comprises at least oneof the following situations:

when it is selected to transmit PHRs on an uplink carrier with a longersubframe duration, the PHR of other uplink carriers with relativelyshorter TTI is calculated based on the first scheduled shorter TTIwithin the first reference subframe; and

if there is no shorter subframe is scheduled within the first referencesubframe, reporting a PHR of the first shorter TTI within the firstreference subframe, or reporting a PHR of any shorter TTI within thefirst reference subframe, and/or reporting an index of a TTI.

Another embodiment of the present invention provides a user equipment(UE) for power allocation, comprising:

a powder determination module, configured to receive uplink schedulinginformation, and determine a corresponding uplink transmit power on eachuplink carrier according to the uplink scheduling information; and

an adjustment module, configured to, according to an actual maximumuplink transmit power of a first reference subframe of the UE and apredefined first priority, adjust the determined uplink transmit powerof each uplink carrier, and/or determine whether to transmit an uplinksignal, the first reference subframe being a subframe which isdetermined according to the uplink scheduling information to transmit anuplink channel/signal.

Still another embodiment of the present invention provides a userequipment (UE) for reporting power headroom, comprising:

a selection module, configured to, when conditions for reporting a PowerHeadroom Report (PHR) are satisfied, select, from at least one uplinkcarrier, one uplink carrier for reporting the PHR, and determine orassume an uplink subframe to transmit the PHR, the uplink subframe beinga first reference subframe;

a PHR value determination module, configured to, according to uplinkscheduling information received in or before a second referencesubframe, determine PHR contents of each uplink carrier to be reportedon the first reference subframe, and determine a corresponding PHR valueaccording to the PHR contents; or, determine the PHR contents of theuplink carrier, according to whether the carrier is a carrier adoptingtwo-step scheduling;

a report module, configured to generate a PHR of each uplink carrieraccording to the determined PHR value of each uplink carrier, and reportthe generated PHR of each uplink carrier on the selected uplink carrierand in the selected first reference subframe.

In an embodiment of the present invention, in view of adopting subframeswith different lengths on more than one carrier of a UE in acommunication system, a power allocation method is provided, in whichthe UE determines a corresponding uplink transmit power on each uplinkcarrier according to the uplink scheduling information, and adjusts,according to the predicted maximum uplink transmit power of the userequipment and a predefined first priority, the transmit power of eachuplink carrier and/or determines whether to transmit an uplink signal ordrop an uplink signal. Hence, the effective allocation of uplink powerof the UE is realized under limited uplink processing time, and theuplink scheduling efficiency of the UE is improved. As a result, theoverall network efficiency is improved.

In another embodiment of the present invention, a UE selects, from atleast one uplink carrier, one uplink carrier for reporting a PHR, anddetermines an uplink subframe to transmit the PHR, the uplink subframebeing a first reference subframe; according to uplink schedulinginformation received in or before a second reference subframe oraccording to whether the carrier is scheduled by two-step scheduling,PHR contents of the uplink carrier are determined, and PHR contents ofeach uplink carrier to be reported in the first reference subframe aredetermined; and, a PHR of each uplink carrier is generated according tothe PHR contents, and the generated PHR of each uplink carrier isreported on the selected uplink carrier and in the determined firstreference subframe. In a case where the subframes are with differentlengths on a multiple carriers of the UE in the communication system, amethod for reporting a PHR is provided. It is ensured that the UE canperform efficient power headroom calculation under limited uplinkprocessing time, so that the accuracy of reporting the PHR is improved.As a result, the uplink scheduling efficiency of the UE is improved.

The above solutions as provided in the present invention just make minormodifications to the existing systems, and hence will not influence thesystem compatibility. Moreover, the implementations of these solutionsas provided are both simple and highly efficient.

Additional aspects and advantages of the present invention will bepartially appreciated and become apparent from the description below, orwill be well learned from the practices of the present invention.

Advantageous Effects of Invention

According to the embodiments of the present invention, procedures ofreporting power headroom report (PHR) and corresponding schedulinguplink resources can be enhanced.

According to other embodiments of the present invention, adjustingtransmit power for different carriers with different TTI lengths can beefficiently performed in a 5G system.

BRIEF DESCRIPTION OF DRAWINGS

The above and/or additional aspects and advantageous of the presentinvention will become apparent and be more readily appreciated from thefollowing descriptions of embodiments, with reference to theaccompanying drawings, in which:

FIG. 1 is a schematic diagram of a combined arrangement scenario oflicensed frequency bands and unlicensed frequency bands in the priorart;

FIG. 2 is a flowchart of a power allocation method according toEmbodiment 1 of the present application;

FIG. 3 is a first schematic diagram of a power adjustment methodaccording to Embodiment 1 of the present application;

FIG. 4 is a second schematic diagram of the power adjustment methodaccording to Embodiment 1 of the present application;

FIG. 5 is a third schematic diagram of the power adjustment methodaccording to Embodiment 1 of the present application;

FIG. 6 is a fourth schematic diagram of the power adjustment methodaccording to Embodiment 1 of the present application;

FIG. 7 is a fifth schematic diagram of the power adjustment methodaccording to Embodiment 1 of the present application;

FIG. 8 is a flowchart of a method for reporting power headroom accordingto Embodiment 2 of the present application;

FIG. 9 is a first schematic diagram of a PHR calculation methodaccording to Embodiment 2 of the present application;

FIG. 10 is a second schematic diagram of the PHR calculation methodaccording to Embodiment 2 of the present application;

FIG. 11 is a third schematic diagram of the PHR calculation methodaccording to Embodiment 2 of the present application;

FIG. 12 is a fourth schematic diagram of the PHR calculation methodaccording to Embodiment 2 of the present application;

FIG. 13 is a fifth schematic diagram of the PHR calculation methodaccording to Embodiment 2 of the present application;

FIG. 14 is a sixth schematic diagram of the PHR calculation methodaccording to Embodiment 2 of the present application;

FIG. 15 is a seventh schematic diagram of the PHR calculation methodaccording to Embodiment 2 of the present application;

FIG. 16 is an eighth schematic diagram of the PHR calculation methodaccording to Embodiment 2 of the present application;

FIG. 17 is a first schematic diagram of a PHR calculation methodaccording to Embodiment 3 of the present application;

FIG. 18 is a second schematic diagram of the PHR calculation methodaccording to Embodiment 3 of the present application;

FIG. 19 is a third schematic diagram of the PHR calculation methodaccording to Embodiment 3 of the present application;

FIG. 20 is a fourth schematic diagram of the PHR calculation methodaccording to Embodiment 3 of the present application;

FIG. 21 is a ninth schematic diagram of the PHR calculation methodaccording to Embodiment 2 of the present application;

FIG. 22 is a structural diagram of a user equipment for power allocationaccording to Embodiment 4 of the present application; and

FIG. 23 is a structural diagram of a user equipment for reporting powerheadroom according to Embodiment 5 of the present application.

MODE FOR THE INVENTION

With the increasingly sharp contradiction between the burst of users'demands for high-bandwidth wireless services and the scarcity offrequency spectrum resources, mobile operators begin to considerlicense-free frequency bands (also referred to as unlicensed frequencybands) as supplements for licensed frequency bands. Therefore, studyingthe deployment of a Long Term Evolution (LTE) network on an unlicensedfrequency band has been put on the agenda. The 3GPP has already began tostudy on how to effectively improve the utilization rate of the wholefrequency spectrum through the effective carrier aggregation of theunlicensed frequency bands and the licensed frequency bands, withoutsignificantly influencing other technologies of the unlicensed frequencybands. FIG. 1 is a schematic diagram of a combined arrangement scenarioof licensed frequency bands and unlicensed frequency bands.

An unlicensed frequency band is generally allocated for some otherpurposes, for example, radar or Wireless Fidelity (WiFi) of 802.11series. Thus, the interference level on the unlicensed frequency band isuncertain, and consequently, it is generally difficult to ensure theQuality of Service (QoS) of the LTE transmission. Despite this, theunlicensed frequency band can still be used for data transmission thatrequires a low QoS. Here, an LTE system deployed on the unlicensedfrequency band is called a Licensed-Assisted Access (LAA) system. How toavoid the mutual interference between the LAA system and a radar, WiFior other wireless systems on the unlicensed frequency band is a criticalissue. A Carrier Sensing (CS) is a collision avoidance mechanismuniversally adapted on the unlicensed frequency band. A mobile stationhas to detect a wireless channel before transmitting signals, and canoccupy the wireless channel to transmit signals only when detecting thatthe wireless channel is idle. This mechanism is called Listen BeforeTalk (LBT). The LAA system also needs to follow the LBT mechanism toensure less interference to other signals. In the LAA system, the uplinktransmission of a User Equipment (UE) is still scheduled by a basestation. However, since the base station and the UE are located atdifferent geographical locations and suffer different interferences, thebase station cannot predict whether the UE can perform transmission in ascheduled subframe when the base station schedules the UE. In order toincrease the transmission probability of the UE on the scheduled uplinksubframe, the base station can adopt two-step scheduling, so as totrigger the UE to transmit an uplink when it is more advantageous forthe UE to occupy a channel. For example, the base station can transmit afirst scheduling signaling at moment t₀ in order to indicate resourceinformation for the uplink transmission of the UE, for example, PhysicalResource Blocks (PRBs), a Modulation and Coding Scheme (MCS) and thelike. Upon receiving the first scheduling signaling, the UE can startpreparing a corresponding uplink signal/channel, but the UE does notexecute the uplink transmission. The base station can transmit a secondscheduling signaling at moment t₁ in order to trigger the UE to performthe uplink transmission on the indicated or predefined subframe (atmoment t₂), and the transmitted uplink signal/channel is the uplinksignal/channel prepared by the UE upon receiving the first schedulingsignaling. To ensure that the UE has enough time to prepare the uplinksignal/channel, the time span from the moment t₀ of receiving the firstscheduling signaling to the moment t₂ of eventually transmitting theuplink signal needs to satisfy a minimum time delay Δt. For example, inaccordance with the time delay of the LTE, Δt=4 ms. Since the secondscheduling signaling is merely for triggering, the time span from themoment t1 of receiving the second scheduling signaling to the moment t₂of eventually transmitting the uplink signal needs to satisfy a minimumtime delay Δt′ which can be less than Δt. For example, Δt′ is 1 ms or 2ms.

When the UE operates in a carrier aggregation mode, the maximum uplinktransmit power is related to the number of simultaneously transmitteduplink carriers. It is not hard to see, when the base station adopts thetwo-step scheduling, the time of receiving the first/second schedulingsignaling by different uplink carriers may be different, but the timefor the UE to eventually transmit uplink signals on these uplinkcarriers is the same. In an existing LTE system, since there is onlyone-step uplink scheduling and the time delay from the uplink schedulingto the uplink transmission is fixed, the UE can determine, in a subframesatisfying the minimum time delay, for example, in a subframe n−4,whether a corresponding uplink signal is transmitted on different uplinkcarriers in an uplink subframe n, so that the maximum transmit power ofthe subframe n can be determined on the subframe n−4, and the powerallocation and adjustment can be performed on each uplink carrier whichis to transmit the uplink signal in the subframe n. In the LAA system,if the base station adopts the two-step scheduling, regardless of whenthe UE receives the first scheduling signaling, the UE can determine howmany uplink carriers to be simultaneously transmitted in the uplinksubframe n only when receiving the second scheduling signaling, so thatthe maximum transmit power of the uplink subframe n is determined. Inaccordance with the method for the existing LTE system, the UE is unableto adjust the power of each carrier in time according to the secondscheduling signaling. Furthermore, in the LTE system, in order tosupport services having low-latency requirements, shorter subframes aredesigned. For example, instead of the 1 ms subframe duration in theconventional LTE, a time length of half a millisecond or less is used asa scheduling unit (TTI). Generally, the shorter the TTI length is, theshorter the minimum time delay from the uplink scheduling to the uplinktransmission is. For example, the time delay under a TTI of 0.5 ms ishalf of 1 ms. Then, within a same time window, it is likely to transmitsignals with different TTI lengths on each uplink carrier, and the timedelay from the uplink scheduling for scheduling these signal to theuplink transmission is also different. For example, on an uplink carrierCC1, a scheduling signaling from a subframe n schedules the uplinktransmission in a subframe n+4, and the TTI length is 1 ms; while on anuplink carrier CC2, a scheduling signaling from a subframe n+2 schedulesthe uplink transmission on the subframe n+4, and the TTI length is 0.5ms. Then, in accordance with the method for the existing LTE system, theUE is unable to adjust the power of uplink carriers on CC1 in timeaccording to the scheduling signaling on the uplink carrier CC2.Similarly, in a 5G system, it is also likely to transmit signals withdifferent TTI lengths on different carriers. For example, one carrier isan LTE carrier having a subcarrier spacing of 15 KHz and a TTI length of1 ms, while another carrier is a 5G carrier having a subcarrier spacingof 30 KHz and a TTI length of 0.5 ms. Then, the power adjustment suffersfrom a similar problem. Therefore, it is urgent to provide a novel poweradjustment method.

In addition, in the LTE system, in order to provide a reference for thebase station in scheduling uplink resources, the UE reports theremaining power headroom in a specified scheduling situation by using aPower Headroom Report (PHR). When the UE needs to report PHRs, that is,when the trigger conditions for reporting the PHRs are satisfied, the UEneeds to report PHRs of all activated uplink carriers. Wherein, the UEneeds to determine in which uplink subframe the PHRs (including PHRs ofall activated uplink carriers) are to be transmitted. For example, ifthe UE is scheduled for uplink transmission on an uplink subframe n, andthis uplink transmission is sufficient to bear the PHRs and is aninitial transmission, the UE can transmit the PHRs on this uplinksubframe n. The UE needs to calculate, according to the uplinktransmission situations of all activated carriers in the uplink subframen, a PHR of each carrier and then generate a PHR report. A specificmethod for calculating a PHR in the existing LTE system can be obtainedby referring to the formulae and descriptions thereof in 5.1.1.2 in TS36.213. Since the generation of the PHR report takes certain processingtime, UE needs to calculate, before the uplink subframe n, for example,starting from the subframe n−4 in which a uplink scheduling signalingfor scheduling the uplink subframe n has been received, the transmitpower of the uplink subframe n according to the uplink schedulingsignaling, and then determine the PHR type according to whether theuplink scheduling signaling is received. For example, if the UE has notreceived a signaling for scheduling the UE to transmit an uplink in asubframe n on a carrier C_(i), the PHR of the carrier C_(i) is a virtualPHR; or otherwise, the PHR of the carrier C_(i) is a real PHR. The UEgenerates a PHR report after determining the PHR type and calculatingthe PHR value. If the base station schedules the two-step scheduling foran uplink carrier, it is possible that the carrier determined by the UEto transmit the PHR report is scheduled by the one-step scheduling inthe conventional LTE, for example, the carrier is a licensed carrier,but carriers contained in the PHR report are scheduled by the two-stepscheduling. It is also possible that the carrier determined by the UE totransmit the PHR report is scheduled by the two-step scheduling, but thetime of receiving a two-step scheduling signaling by each carriercontained in the PHR report is different, or the minimum time delay fromuplink scheduling to uplink transmission is different for a multiple ofcarriers contained in the PHR report. Therefore, it is urgent to providea novel PHR calculation and report method.

Embodiments of the present invention will be described in detailhereinafter. The examples of these embodiments have been illustrated inthe accompanying drawings throughout which same or similar referencenumerals refer to same or similar elements or elements having same orsimilar functions. The embodiments described with reference to theaccompanying drawings are illustrative, merely used for explaining thepresent invention and should not be regarded as any limitations thereto.

Embodiment 1

In this embodiment, a specific way of determining an actual transmitpower of each uplink transmitting carrier to transmit an uplink signalis as follows.

A UE adjusts the transmit power of each uplink transmitting carrieraccording to the received uplink scheduling information and/or thepredicted maximum uplink transmit power of the user equipment (UE), andadjusts the power on the corresponding uplink carrier and/or determineswhether to drop transmitting an uplink signal according to the maximumuplink transmit power during the actual transmission and a predefinedpriority criterion.

FIG. 2 shows a specific flow of the power allocation method provided inthis embodiment. The method comprises the following steps.

Step 201: A UE receives uplink scheduling information, then determines acorresponding uplink transmit power on each uplink carrier according tothe uplink scheduling information, and prepares uplink transmissiondata, where a first reference subframe is a subframe which is determinedaccording to the uplink scheduling information to transmit an uplinkchannel/signal.

Preferably, on an uplink carrier, the UE can operate in a one-stepscheduling mode, i.e., in an existing LTE scheduling mode. A basestation transmits an uplink scheduling signaling in a subframe t₀ toindicate the UE to transmit an uplink channel/signal in a subframe t₂.The frequency-domain resource allocation, the modulation and codingscheme, the power control method and the like of the transmitted uplinkchannel/signal are all indicated by the uplink scheduling signaling, andthe uplink transmission time is also indicated by the uplink schedulingsignaling. For example, a time interval between a subframe in which theuplink scheduling signaling is received and a subframe for transmittingan uplink channel/signal scheduled by the uplink scheduling signaling ispredefined by the system, or is dynamically indicated by the uplinkscheduling signaling. The time interval between the uplink schedulingsignaling and the transmission of the uplink channel/signal is not lessthan a minimum processing time delay Δt.

On an uplink carrier, the UE can also operate in a two-step schedulingmode. In other words, a base station transmits a first schedulingsignaling in a subframe t₀ to indicate the resource allocation,modulation and coding information of the uplink channel/signal to betransmitted by the UE, and/or power control information, and/orinformation about the transmission time. The base station cansemi-statically configure the scheduling as one-step scheduling ortwo-step scheduling. The base station can also dynamically configure thescheduling as one-step scheduling or two-step scheduling, for example,by using a predefined bit in the UL grant or a predefined RNTI in the ULgrant. It is to be noted that, the information about the transmissiontime does not shows the time of indicating the UE to transmit the uplinkchannel/signal. For example, the UE cannot determine the transmissiontime of the scheduled uplink channel/signal merely depending upon thetime information. The time information can only comprise a time offsetof the transmission time of the scheduled uplink channel/signal withrespect to the second scheduling signaling. After the subframe t₀, thebase station selects, according to a scheduling algorithm, a proper timeto trigger the UE to transmit the uplink channel/signal scheduled by thefirst scheduling signaling. In other words, the base station transmits asecond scheduling signaling in a subframe t₁ to trigger the transmissionof the uplink channel/signal. The second scheduling signaling can be acell-specific trigger signaling, or a UE-group trigger signaling, or aUE-specific trigger signaling. This is not limited in the presentinvention. The second scheduling signaling triggers the UE to transmitthe uplink channel/signal scheduled by the first scheduling signaling ina subframe t₂. The second scheduling signaling can contain only atrigger signaling, but also information indicative of the transmissiontime, and/or contain power control information and the like. It isassumed that a minimum time interval from the second schedulingsignaling to the transmission of the uplink channel/signal by the UE isΔt′. Generally, Δt′<Δt. In other words, the minimum processing timedelay Δt′ between the uplink scheduling signaling of the secondscheduling signaling for two-step scheduling and the transmission of theuplink channel/signal is generally less than the minimum processing timedelay Δt between the scheduling signaling for one-step scheduling andthe transmission of the uplink channel/signal.

It is to be noted that, for a same UE, on different carriers, theminimum processing time delay from the receipt of a scheduling signalingto the transmission of the scheduled uplink channel/signal by the UE maybe different. For example, as described above, if the two-stepscheduling is adopted, the minimum processing time delay Δt′ between thesecond scheduling signaling for two-step scheduling and the transmissionof the uplink channel/signal is generally less than the minimumprocessing time delay Δt between the scheduling signaling for one-stepscheduling and the transmission of the uplink channel/signal. Thus, ifat least one of a multiple of carriers configured for the UE scheduledby the two-step scheduling while at least one of the carriers scheduledby the one-step scheduling, the minimum processing time delay of the UEon the multiple of carriers is different. For another example, even inthe one-step scheduling (also possibly in the two-step scheduling), inorder to support transmission with a low transmission latency, or in the5G mobile communication technology system, a multiple of carriers forthe UE may adopt scheduling unit TTIs (Transmission Time Intervals) withdifferent lengths. For example, one carrier has a conventional TTIlength of 1 ms, while another carrier, for example, can support a TTIlength of 0.25 ms in order to support the low-latency transmission. Adifferent TTI length may be achieved by a different subcarrier spacing.For example, if a time slot has seven OFDM symbols, a TTI lengthcorresponding to a subcarrier spacing of 15 KHz is 0.5 ms and a TTIlength corresponding to a subcarrier spacing of 60 KHz is 0.125 ms. Adifferent TTI length may also be achieved by a same subcarrier spacingand a different number of OFDM symbols. For example, also at asubcarrier spacing of 15 KHz, the TTI length of a carrier is a time slothaving seven OFDM symbols and the TTI length of another carrier is amini time slot having two OFDM symbols. Hence, the minimum processingtime delay of the UE on a carrier having a short TTI length is less thanthe minimum processing time delay on the conventional LTE carrier. Forexample, the minimum processing time delay on a carrier with 1 ms TTI isX ms, while the minimum processing time delay on a carrier with 0.25 msTTI is about X/4 ms. A specific way of configuring the TTI length canbe: semi-statically configuring some subframes on a certain carrier atTTIs of a length and other subframes at TTIs of another length, orconfiguring the TTI length of a subframe in real time by a dynamicsignaling, or in other ways. The way of configuring the TTI length isnot limited in the present invention.

In this step, the UE receives uplink scheduling information from acontrol node. The uplink scheduling information is uplink schedulinginformation in the one-step scheduling, or a first scheduling signalingin the two-step scheduling.

The UE can prepare an uplink transmit power according to the uplinkscheduling information by at least one of the following ways.

Way 1: The UE determines, according to the received uplink schedulingsignaling and on a corresponding uplink carrier, a UE transmit powerexpected by the base station, compares the UE transmit power with amaximum transmit power Pcmax,c of the uplink carrier, and uses thesmaller one as the transmit power of the UE.

For example, the UE transmit power expected by the base station iscalculated according to the PUSCH transmit power formula in TS36.213.5.1:

${P_{{PUSCH},c}(i)} = {\min \begin{Bmatrix}{{P_{{CMAX},c}(i)},} \\{10\mspace{14mu} \log_{10}\begin{matrix}{\left( {M_{{PUSCH},c}(i)} \right) + {P_{{O\mspace{14mu} {PUSCH}},c}(j)} +} \\{{{\alpha_{c}(j)} \cdot {PL}_{c}} + {\Delta_{{TF},c}(i)} + {f_{c}(i)}}\end{matrix}}\end{Bmatrix}}$

where M_(PUCSH,c)(i), Δ_(TF,c)(i) and f_(c) (i) are directly orindirectly obtained from the uplink scheduling information. Specificmeanings of the parameters refer to the explanation in TS 36.213.5.1.

Preferably, for a UE scheduled by the two-step scheduling, if the UEstarts adjusting power upon receiving the first scheduling signaling,then, Way 1 is more suitable for the UE. Since the UE cannot determinewhen to transmit the scheduled uplink channel/signal upon receiving thefirst scheduling signaling and thus cannot determine the maximumtransmit power Pcmax of the UE in transmitting the uplinkchannel/signal, at this stage, the UE cannot further adjust the transmitpower on each carrier according to the Pcmax so that the power of thesimultaneously transmitted carriers does not exceed the Pcmax.

Of source, it is not executed that a UE adopting the one-step schedulingcan adopt this way.

Way 2: Step 1: The UE determines, according to the received firstscheduling information and on a corresponding uplink carrier, a UEtransmit power expected by the base station, compares the UE transmitpower with the Pcmax,c of the uplink carriers, and uses the smaller oneas the transmit power of the UE. Step 2: The UE determines whether thesum of the transmit power on all uplink carriers scheduled fortransmission exceeds the maximum transmit power Pcmax′ predicted by theUE; and, if exceed, the power of a corresponding uplink carrier isadjusted according to a predefined second priority, so that the sum ofpower on all uplink carriers does not exceed the Pcmax′. The two stepsare not necessarily performed temporally in two steps, and can besimultaneously performed temporally.

It is not hard to see that, step 1 of Way 2 is Way 1, where for eachuplink carrier, the power on each uplink carrier is determinedseparately according to the Pcmax,c of each uplink carrier and theuplink scheduling information from the base station; while in step 2 ofWay 2, the power of each uplink carrier is further adjusted according tothe total maximum transmit power Pcmax′ assumed by the UE.

Preferably, the second priority can be in accordance with the prior art.For example, the priority of a carrier containing uplink controlinformation is higher than that of a carrier containing no uplinkcontrol information. The second priority can also be a newly definedpriority. For example, the priority of a licensed carrier is higher thanthat of an unlicensed carrier; or, the priority of a carrier to beabsolutely transmitted is higher than that of a carrier to be possiblytransmitted; and the like.

Preferably, Way 2 is more suitable for a UE adopting the one-stepscheduling, particularly a UE that performs both bit preparation andpower preparation of the uplink signal/channel. The UE can determine thetransmission time of the scheduled uplink channel/signal upon receivingthe uplink scheduling signaling. Therefore, the UE can at least predictthe Pcmax′ of a subframe t₂ (called the first reference subframe) fortransmitting the scheduled uplink channel/signal in accordance with apredefined method, and further adjust the power of each uplink carrieron the basis of the Pcmax′. It is assumed that the UE starts to preparea subframe t of the scheduled uplink channel/signal as a secondreference subframe after receiving the uplink scheduling signaling.Preferably, the time difference between the second reference subframeand the first reference subframe is equal to the minimum processing timedelay for processing the PUSCH on this carrier. Although the minimumprocessing time delay Δt or Δt′ on each carrier may be different, afterthe second reference subframe, the base station may still schedule otheruplink carriers to perform transmission on the subframe t₂, for example,schedule a TTI with a smaller minimum processing time delay, so that thePcmax for the subframe t₂ is different from the Pcmax′ predicted by theUE. If the UE has no time to adjust power according to the actual Pcmax(e.g., step 202), Way 2 still cannot completely overcome the UE powerwaste or the loss of UE uplink transmission resulted from the differencebetween the actual Pcmax and the predicted Pcmax′. However, comparedwith Way 1, Way 2 can reduce the UE power waste or the possibility ofgiving up transmitting the uplink signal to a certain extent.

In step 2, the UE can predict the total transmit power Pcmax′ of the UEin the first reference subframe by one of the following methods, andthen perform the power adjustment on the corresponding carrier based onthe total transmit power Pcmax′. Generally, in the one-step schedulingmethod, the second reference subframe is a subframe next to a subframein which the uplink scheduling signaling is received. For example, ifthe UE receives the uplink scheduling signaling in a subframe t₀, the UEstarts preparing, in a subframe t₀₊₁, the uplink channel/signalscheduled by the uplink scheduling signaling. Alternatively, in theone-step scheduling method, the second reference subframe is not earlierthan the subframe receiving the uplink scheduling signaling, and thetime difference between the second reference subframe and the firstreference subframe is equal to the minimum processing time delay for theUE to process the PUSCH on this carrier.

Method (a): When predicting the total transmit power of the firstreference subframe, only an uplink carrier, which can be determinedbefore the second reference subframe to perform transmission in thefirst reference subframe, is considered as a transmitting carrier, andthe transmit power of the transmitting carrier is calculated.

As an implementation, regardless of whether the uplink carriereventually transmits an uplink channel/signal in the first referencesubframe, the UE determines, only according to the received schedulingsignaling before the second reference subframe, whether thecorresponding carrier performs transmission in the first referencesubframe. In other words, when and only when the UE has received theuplink scheduling signaling of the corresponding carrier before thesecond reference subframe and the scheduling signaling indicates thatthe UE transmits the uplink channel/signal in the first referencesubframe, the uplink carrier is considered as a transmitting uplinkcarrier, and other uplink carriers are all considered as not to performtransmission.

Preferably, for an uplink carrier by the one-step scheduling, if the UEhas received an uplink scheduling signaling UL grant for schedulingtransmission in the first reference subframe before the second referencesubframe, the uplink carrier is considered as a transmitting uplinkcarrier; or otherwise, the uplink carrier is considered as anon-transmitting uplink carrier.

Preferably, for an uplink carrier scheduled by the two-step scheduling,if the UE has received the second scheduling signaling before the secondreference subframe, the uplink carrier is considered as a transmittinguplink carrier when the uplink transmission triggered by the secondscheduling signaling is performed in the first reference subframe; orotherwise, the uplink carrier is considered as a non-transmitting uplinkcarrier.

Preferably, for an uplink carrier scheduled by the two-step scheduling,if the UE has not received the second scheduling signaling or the firstscheduling signaling before the second reference subframe, the uplinkcarrier is considered as a non-transmitting uplink carrier.

In a specific application scenario, as shown in FIG. 3, the base stationconfigures two uplink carriers for the UE, where the CC1 is a licensedfrequency band carrier and the CC2 is an unlicensed frequency bandcarrier. It is assumed that the CC1 is scheduled by one-step schedulingg while the CC2 is scheduled by two-step scheduling. The UE receives, ina subframe t₀ (a subframe t−1 in this example), a schedule for allowingthe carrier CC1 to transmit a PUSCH in a first reference subframe t₂.The UE starts preparing the transmission of the PUSCH in a subframe t,and it is required to predict the total transmit power of all carriersof the UE in the subframe t₂. Since the UE has not received the secondscheduling information in spite of having received the first schedulinginformation for the CC2 before the start of the subframe t, the UE isunable to know whether the CC2 will transmit an uplink channel/signal inthe subframe t₂. Consequently, the UE can only assume that the CC2 willnot transmit an uplink channel/signal in the subframe t₂ while the CC1will transmit an uplink channel/signal in the subframe t₂, so as todetermine the maximum transmit power of the UE. Furthermore, the maximumtransmit power is compared with the power of the CC1 determined bytaking Pcmax,c as an upper limit, so that the power of the CC1 cannotexceed the maximum transmit power.

In another specific application scenario, as shown in FIG. 4, the basestation configures two uplink carriers for the UE, where the CC1 carrierhas a TTI length of 1 ms and the CC2 carrier has a TTI length of 0.25ms. The two carriers both adopt one-step scheduling. The minimum timedelay from the scheduling signaling of the CC1 carrier to the uplinktransmission is 4 ms, and the minimum time delay from the schedulingsignaling of the CC2 carrier to the uplink transmission is 1 ms. The UEreceives, in a subframe t₀ (a subframe t−1 in this example), a schedulefor allowing the carrier CC1 to transmit a PUSCH on a first referencesubframe t₂. The UE starts preparing the transmission of the PUSCH in asubframe t, and it is required to predict the total transmit power ofall uplink carriers of the UE in the subframe t₂. Since the UE has notreceived scheduling information for the CC2 before the start of thesubframe t, the UE is unable to know whether the CC2 will transmit anuplink channel/signal in the subframe t₂. Consequently, the UE can onlyassume that the CC2 will not transmit an uplink channel/signal in thesubframe t₂ while the CC1 will transmit an uplink channel/signal in thesubframe t₂, so as to determine the maximum transmit power of the UE.Furthermore, the maximum transmit power is compared with the power ofthe CC1 determined by taking Pcmax,c as an upper limit, so that thepower of the CC1 cannot exceed the maximum transmit power. In thisexample, for the transmission of uplink data of the carrier CC2, themaximum total transmit power of the UE can be determined according tothe transmissions of the CC1 and the CC2. The UE has received ascheduling signaling for the CC1 when receiving an uplink schedulingsignaling for the carrier CC2. Thus, the transmission condition of theCC1 and the required uplink power can be determined, and the total powerof the UE in the first reference subframe can be determined. If the sumof the power of the CC1 and the power of the CC2 exceeds the maximumtransmit power of the UE, the UE can adjust the power of the CC2according to a predefined rule, so that the sum of the power of the CC1and the power of the CC2 does not exceed the maximum transmit power. Forexample, it is possible to ensure, according to the first priority rulein step 202, that a carrier with a maximum processing time delay fromthe receipt of the scheduling signaling by the UE to the transmission ofthe scheduled uplink channel/signal by the UE has a higher priority,that is, the power of the CC1 is ensured while the power of the CC2 isreduced; or, it is also possible to ensure, according to whether aservice with higher performance requirements is contained, for example,the time delay requirements for the ultra-reliable and low-latencycommunications (URLLC) services should be more stringent than those forcommon enhanced mobile broadband (eMBB) services. For example, accordingto the first priority rule in step 202, that a carrier with a shorterscheduling unit length has a higher priority, that is, the power of theCC2 is ensured. If the priority of the CC1 is lower, it is required toreduce the power. However, if the CC1 has not enough time to reduce itspower, there is no choice other than dropping transmitting the CC1.

Method (b): When predicting the total transmit power of the UE in thesubframe t₂, an uplink carrier which can be determined in or before thesecond reference subframe to transmit a PUSCH in the first referencesubframe and an uplink carrier which possibly transmits a PUSCH in thefirst reference subframe are calculated.

As an implementation, for an uplink carrier which can be determined inor before the second reference subframe not to transmit a PUSCH on thefirst reference subframe, the UE determines the uplink carrier as anon-transmitting uplink carrier; however, for an uplink carrier whichcan be determined in or before the second reference subframe to transmita PUSCH in the first reference subframe or an uplink carrier whichpossibly transmits a PUSCH in the first reference subframe, the UEdetermines the uplink carrier as a transmitting uplink carrier.

Preferably, for an uplink carrier by the one-step scheduling, if the UEhas received a UL grant signaling for scheduling transmission in thefirst reference subframe before the second reference subframe, theuplink carrier is considered as a transmitting uplink carrier; orotherwise, the uplink carrier is considered as a non-transmitting uplinkcarrier.

Preferably, for an uplink carrier scheduled by the two-step scheduling,if the UE has received the second scheduling signaling before the secondreference subframe, the uplink carrier is considered as a transmittinguplink carrier when the uplink transmission triggered by the secondscheduling signaling is performed in the first reference subframe; orotherwise, the uplink carrier is considered as a non-transmitting uplinkcarrier.

Preferably, for an uplink carrier scheduled by the two-step scheduling,if the UE has received the first scheduling signaling but not the secondscheduling signaling in or before the second reference subframe, the UEcan determine, according the first scheduling signaling, whether theuplink carrier is a transmitting uplink carrier. For example, if thereceived first scheduling signaling indicates that the uplinktransmission is absolutely impossible to be performed in the firstreference subframe, the UE can determine the corresponding uplinkcarrier as a non-transmitting uplink carrier. And/or, if the UE cannotexclude the possibility of performing uplink transmission in the firstreference subframe by using the received first scheduling signaling, theUE decides that the uplink carrier is a transmitting uplink carrier.

Preferably, for an uplink carrier scheduled by the two-step scheduling,if the UE has not received the first scheduling signaling in or beforethe second reference subframe, the UE determines the correspondinguplink carrier as a non-transmitting uplink carrier.

In a specific embodiment, as shown in FIG. 3, the base stationconfigures two uplink carriers for the UE, where the CC1 is a licensedfrequency band carrier and the CC2 is an unlicensed frequency bandcarrier. It is assumed that the CC1 is scheduled by one-step schedulingwhile the CC2 is scheduled by two-step scheduling. The UE receives, in asubframe t₀ (a subframe t−1 in this example), a schedule for allowingthe carrier CC1 to transmit a PUSCH in a first reference subframe t₂.The UE starts preparing the transmission of the PUSCH in a subframe t,and it is required to predict the total transmit power of all carriersof the UE in the subframe t₂. Since the UE has received first schedulinginformation for the CC2 but not received second scheduling informationbefore the subframe t, the UE is unable to know whether the CC2 willtransmit an uplink channel/signal in the subframe t₂. Despite this, theUE still assumes that the CC2 will transmit an uplink channel/signal inthe subframe t₂ and the CC1 will transmit an uplink channel/signal inthe subframe t₂, so as to determine the maximum transmit power of theUE. Furthermore, the maximum transmit power Pcmax′ assumed by the UE iscompared with the power of the CC1 determined by taking Pcmax,c as anupper limit, so that the power of the CC1 cannot exceed Pcmax′. Thus, arelatively conservative maximum power is obtained by calculating Pcmax′.If the CC2 transmits an uplink channel/signal in the subframe t₂, it canbe no problem to enable the CC1 to perform transmission in accordancewith the adjusted power. However, if the CC2 does not performtransmission in the subframe t₂, the actual maximum transmit power Pcmaxbecomes higher, it is possible that the CC1 makes an unnecessary powerreduction in this step.

Step 202: The UE adjusts, according to an actual maximum uplink transmitpower Pcmax of the first reference subframe and a first priority, thetransmit power of each uplink carrier, and/or determines whether totransmit an uplink signal.

Preferably, the predefined first priority means that a carrier with amaximum minimum-processing time delay from the receipt of a schedulingsignaling by the UE to the transmission of the scheduled uplinkchannel/signal by the UE has a higher priority.

Preferably, the predefined first priority means that a carrier with ashorter scheduling unit time (TTI) length has a higher priority.

Preferably, the predefined first priority means that a carrierconfigured to adopt one-step scheduling has a higher priority than acarrier configured to adopt two-step scheduling.

Preferably, the predefined first priority means that a licensedfrequency band carrier has a higher priority than an unlicensedfrequency band carrier.

Preferably, the predefined first priority means that an uplink signalcontaining an uplink control signaling has a higher priority than anuplink signal containing no uplink control signaling.

Preferably, the predefined first priority means that a carrier which hasbeen determined to transmit an uplink channel/signal in or before thesecond reference subframe is superior to a carrier which has not beendetermined to transmit an uplink channel/signal before the secondreference subframe.

If the sum of transmit power of the carriers exceeds the actual maximumuplink transmit power of the UE and if the UE has enough time to reducethe power, according to the first priority, the power of a carrierhaving a lower priority can be further reduced to P_(j,c) on the basisof the transmit power P_(i,c) determined in step 201, so that the sum ofpower of all transmitting carriers does not exceed Pcmax. Or, thetransmission of the power having a low priority is dropped. If the UEhas not enough time to perform power adjustment on a carrier whose poweris expected to be reduced, the UE can only drop transmitting a carrierhaving a lower priority, and transmit a carrier having a higher priorityaccording to the transmit power P_(i,c) determined in step 201, so thatthe sum of power of all transmitting carriers cannot exceed Pcmax. As animplementation, the UE can separately perform the bit preparation of theuplink signal and the power adjustment of the uplink signal.

Preferably, the base station can allocate a minimum guaranteed transmitpower Pg for each carrier or a carrier group. When it is not determinedwhether the carrier performs uplink transmission, the power allocated toother carriers cannot exceed Pcmax-Pg. For example, the base stationconfigures three carriers for the UE, where the CC1 and the CC2 forms acarrier group, and the CC3 forms a carrier group. The base stationallocates Pg1 to the carrier group formed by the CC1 and the CC2, andallocates Pg2 to the CC3. When the UE adjusts the uplink power of theCC1 and the CC2, if the UE is unable to determine whether the CC3 mayperform transmission simultaneously, the total power allocated to theCC1 and the CC2 by the UE cannot exceed Pcmax-Pg2. When and only whenthe UE determines that the CC3 will not perform transmissionsimultaneously, the total power which can be allocated to the CC1 andthe CC2 by the UE cannot exceed Pcmax. It is to be noted that the way ofclassifying a carrier group is not limited in the present application.For example, a multiple of carriers with a determined carrier index canbe classified into one carrier group, or a multiple of carriers with asame TTI length can be classified into one carrier group, and so on.

It is to be noted that, in Way 1 of the step 201, the power of eachcarrier is not adjusted with respect to the size of the total power.Thus, it is more possible in the step 202 that the sum of power of thecarriers exceeds the maximum transmit power of the UE. If, for thesecarriers, the UE has no time to adjust the power, the UE needs to ensurethe power of a carrier having a higher priority and drops a carrierhaving a lower priority in accordance with the priority.

In addition, in this embodiment, the UE can be supported to adoptdifferent methods for power control on different carriers. For example,it is assumed that the carriers configured for the UE have a same TTIlength, and some of the carriers are configured to adopt two-stepscheduling while the remaining carriers are configured to adopt one-stepscheduling. Hence, the UE can adopt Way 1 in the step 201 and the step202 with regard to the carriers scheduled by the two-step scheduling,and adopt Way 2 in the step 201 and the step 202 with regard to thecarriers adopting the one-step scheduling. In this embodiment, the UEcan also be supported to adopt a same method for power control on allthe carriers.

In a specific application scenario, as shown in FIG. 5, the base stationconfigures three uplink carriers for the UE, where the CC1 and CC2 arelicensed frequency band carriers and the CC3 is an unlicensed frequencyband carrier. It is assumed that the CC1 and the CC2 is scheduled byone-step scheduling while the CC3 is scheduled by two-step scheduling.If it is assumed that the UE simultaneously prepares an uplinktransmission bit and a transmit power, the required minimum processingtime delay is 4 ms. For all the three carriers, the UE adopts Way 1 inthe step 201: it is assumed that the UE has received, in a subframe t₀(a subframe t−1 in this example), a schedule for allowing the carriersCC1 and CC2 to transmit PUSCHs in a first reference subframe t₂, wherethe PUSCH of the CC1 contains uplink control information while the PUSCHof the CC2 does not contain uplink control information. The UE startspreparing, in a subframe t, the transmission of the PUSCHs of the twocarriers. The minimum time delay required by the UE to prepare theuplink transmission bit and the transmit power is 4 ms. In other words,a time interval between the subframe t and the subframe t₂ is 4 ms. TheUE determines the uplink transmit power of the CC1 according to Pcmax,cof the CC1 and the uplink power scheduled by the base station indicatedby the received scheduling signaling, for example, the power being 10.The UE determines the uplink transmit power of the CC2 according toPcmax,c of the CC2 and the uplink power scheduled by the base stationindicated by the received scheduling signaling, for example, the powerbeing 12. Before the subframe t, the UE has received the firstscheduling information for the CC3 but not received the secondscheduling information, so the UE is unable to know whether CC3 willtransmit an uplink channel/signal in the subframe t₂. The UE determinesthe uplink transmit power of the CC3 according to Pcmax,c of the CC3 andthe uplink power scheduled by the base station indicated by the receivedfirst scheduling signaling, for example, the power being 8. The UEreceives, in a subframe t₃, a second scheduling signaling for the CC3,and determines that the UE also transmits, in the first referencesubframe t₂, a PUSCH containing no uplink control information on theCC3. The UE determines, according to the information about the PUSCHs tobe transmitted by the three CCs, Pcmax of the first reference subframet₂, for example, 20. Hence, in the step 202, according to the predefinedpriority, for example, the uplink control signaling is superior to aPUSCH containing no uplink control signaling, the UE determines thepriority is CC1>CC2=CC3. Therefore, the power of the CC1 is firstensured to be 10, and the remaining power of 20−10=10 can be used fortransmitting the CC2 or CC3. Since the CC2 requires a power of 12 andthe CC3 requires a power of 8, the UE transmits the CC1 and the CC3 andgives up transmitting the CC2.

In another specific application scenario, the base station configuresthree uplink carriers for the UE, where the CC1 and the CC2 are licensedfrequency band carriers and the CC3 is an unlicensed frequency bandcarrier. It is assumed that the CC1 and the CC2 is scheduled by one-stepscheduling while the CC3 is scheduled by two-step scheduling. If it isassumed that the UE simultaneously prepares an uplink transmission bitand a transmit power, the required minimum processing time delay is 4ms. For the carriers CC1 and CC2, the UE adopts the method (a) in Way 2in the step 201; while for the carrier CC3, the UE adopts Way 1 in thestep 201: it is assumed that the UE receives, in a subframe t₀ (asubframe t−1 in this example), a schedule for allowing the carriers CC1and CC2 to transmit PUSCHs in the first reference subframe t₂, where thePUSCH of the CC1 contains uplink control information while the PUSCH ofthe CC2 does not contain uplink control information. The UE startspreparing, in a subframe t, the transmission of the PUSCHs of the twocarriers. The minimum time delay required by the UE to prepare theuplink transmission bit and the transmit power is 4 ms. In other words,a time interval between the subframe t and the subframe t₂ is 4 ms. TheUE determines the uplink transmit power of the CC1 according to Pcmax,cof the CC1 and the uplink power scheduled by the base station indicatedby the received scheduling signaling, for example, the power being 10.The UE determines the uplink transmit power of the CC2 according toPcmax,c of the CC2 and the uplink power scheduled by the base stationindicated by the received scheduling signaling, for example, the powerbeing 12. Before the subframe t, the UE has received the firstscheduling information for the CC3 but not received the secondscheduling information, so the UE is unable to know whether CC3 willtransmit an uplink channel/signal in the subframe t₂. The UE determinesthe uplink transmit power of the CC3 according to Pcmax,c of the CC3 andthe uplink power scheduled by the base station indicated by the receivedfirst scheduling signaling, for example, the power being 8. While in thesecond reference subframe, the UE assumes Pcmax′ of the first referencesubframe is calculated based on the assumption of transmitting the CC1and the CC2 and not transmitting the CC3 in the first referencesubframe, wherein the Pcmax′ is e.g., 21. Hence, according to the secondpriority, CC1>CC2, the UE ensures the uplink transmit power 10 of theCC1 and reduces the uplink transmit power of the CC2 to 11, and the UEdoes not adjust the power of the CC3. The UE receives, in a subframe t₃,a second scheduling signaling for the CC3, and determines that the UEalso transmits, on the first reference subframe t₂, a PUSCH containingno uplink control information on the CC3. The UE determines, accordingto the information about the PUSCHs to be transmitted by the three CCs,the actual Pcmax of the first reference subframe t₂, for example, 20.Hence, in the step 202, according to the predefined first priority, forexample, a carrier which is determined to perform transmission in thesecond reference subframe is superior to a carrier which is notdetermined to perform transmission, the UE determines the priority isCC1>CC2>CC3. Therefore, the UE transmits the CC1 and the CC2, and givesup transmitting the CC3. Since the CC3 is not transmitted, Pcmax isstill 21. Therefore, no further adjustment is to be performed on thepower of the CC1 and the power of the CC2.

In the above example, if it is assumed that the UE separately preparesthe uplink transmission bit and the transmit power, the required minimumprocessing time delay is 1 ms. Hence, in the step 201, if the method 1is adopted, the UE separately determines the power of the three CCs as10, 12 and 8. In the step 202, the UE determines the actual Pcmax as 20;and, according to the predefined first priority, for example, whethercontaining the uplink control information, i.e., the priority isCC1>CC2=CC3, the UE determines that the power of the CC1 remainsunchanged and is still 10, and the CC2 and the CC3 equally shares theremaining 10. That is, the UE adjusts the power of the CC2 as 6 and thepower of the CC3 as 4. The UE transmits all the CC1, CC2 and CC3.

In still another specific application scenario, as shown in FIG. 6, thebase station configures two uplink carriers for the UE, where the CC1carrier has a subframe duration of 1 ms and the CC2 carrier has asubframe duration of 0.25 ms. The two carriers both adopt one-stepscheduling. The minimum time delay from the uplink scheduling signalingof the CC1 carrier to the uplink transmission is 4 ms, and the minimumtime delay from the uplink scheduling signaling of the CC2 carrier tothe uplink transmission is 1 ms. The UE receives, in a subframe t₀ (asubframe t−1 in this example), a schedule for allowing the carrier CC1to transmit a PUSCH in a first reference subframe t₂. The UE startspreparing, in a subframe t, the transmission of the PUSCH. In accordancewith the method (a) of Way 2 in the step 201, the UE needs to predictthe total transmit power of the UE in all carriers of the subframe t₂.Since the UE has not received scheduling information for the CC2 beforethe subframe t, the UE is unable to know whether the CC2 will transmitan uplink channel/signal in the subframe t₂. Consequently, the UE canonly assume that the CC2 will not transmit an uplink channel/signal inthe subframe t₂ while the CC1 will transmit an uplink channel/signal inthe subframe t₂, so as to determine the maximum transmit power of theUE, Pcmax′=18. It is determined, according to the Pcmax,c of the CC1 andthe power scheduled by the base station, that the power of the CC1 is12, which does not exceed Pcmax′, so it is not required to furtherreduce the power. The UE receives, in a subframe t₃, a schedulingsignaling for the CC2, and determines to transmit the CC2 in thesubframe t₂. Hence, the UE starts preparing the power of the CC2, anddetermines, according to Pcmax,c of the CC1 and the power scheduled bythe base station, that the power of the CC2 is 10. The UE determines tosimultaneously transmit the CC1 and the CC2 in the subframe t₂, wherePcmax=16. If it is assumed that the first priority rule means that acarrier with a maximum processing time delay from the receipt of ascheduling signaling by the UE to the transmission of the scheduleduplink channel/signal by the UE has a higher priority, the UE ensuresthe power of the CC1. As a result, the power of the CC2 is to be reducedto 16−12=4. In this case, no any additional operation needs to beperformed in the step 202. If the first priority means that a carriercontaining a service with higher performance requirements has a higherpriority, for example, low-latency data (URLLC data) borne by thecarrier CC2, the priority of the CC2 is high. Thus, the power of the CC2should be ensured to be 10, and the remaining power of 16−10=6 can beallocated to the CC1. However, if the CC1 has not enough time to adjustthe power, the transmission of the CC1 is dropped, as shown in FIG. 7.

Embodiment 2

In this embodiment, a specific way of generating, by a UE, a PHR reportof each carrier and transmitting the PHR on the selected carrier is asbelow.

When the conditions for reporting a PHR are satisfied, the UE selects anuplink carrier and an uplink subframe probably used to transmit PHR,then uses the uplink subframe as a PHR calculation reference subframe(called a first reference subframe), and determines, according to uplinkscheduling information received in or before a second referencesubframe, contents of the PHR of each uplink carrier. The UE generates aPHR report according to the determined contents of the PHR, and reportsthe PHR on the selected uplink carrier in the corresponding subframe.

The base station can semi-statically configure the scheduling mode of acertain carrier of the UE as one-step scheduling or two-step scheduling.The base station can also dynamically configure the scheduling mode asone-step scheduling or two-step scheduling, for example, by a predefinedbit in the UL grant or a predefined RNTI in the UL grant.

FIG. 8 shows a specific flow of the method for generating and reportinga PHR provided in this embodiment. The method comprises the followingthe steps.

Step 801: When conditions for reporting a PHR are satisfied, a UEselects, from at least one uplink carrier, one uplink carrier forreporting the PHR, and determines an uplink subframe probably used totransmit the PHR, the uplink subframe being a first reference subframe.

Wherein, the satisfied conditions for reporting a PHR can be conditionsdefined in the existing LTE system, for example, the trigger conditionsin TS 36.321 5.4.6 such as newly activating an uplink carrier, a largechange in downlink path loss, or PHR-timer expire and the like. It is tobe noted that other satisfied conditions for reporting a PHR are alsoapplicable to the present invention and will not be limited herein.

Preferably, the UE can select, after the PHR report conditions aresatisfied, an uplink carrier with initial uplink PUSCH transmission (notretransmission), and the PUSCH is sufficient to transmit a PHR on theuplink carrier bearing the PHR.

Preferably, the UE can select an uplink carrier in a licensed frequencyband to transmit the PHR.

Preferably, the UE can select an uplink carrier in an unlicensedfrequency band to transmit the PHR.

Preferably, the UE shall select to transmit the PHR on a one-stepscheduled PUSCH.

Preferably, the UE can select to transmit the PHR on a one-stepscheduled PUSCH, or transmit the PHR on a two-step scheduled PUSCH.

Preferably, the UE selects a first reference subframe reporting the PHRas a PHR reference subframe. In other words, the PHR calculated by theUE is determined based on the uplink transmission condition of eachcarrier in the first reference subframe assumed by UE.

Preferably, if the UE selects to transmit the PHR on a one-stepscheduled uplink carrier, the first reference subframe is a subframe inwhich UE transmits a PUSCH containing the PHR. If the LBT fails, the UEcannot transmit the PUSCH, but still considers this subframe as thefirst reference subframe.

Preferably, if the UE decides to transmit the PHR on a two-stepscheduled uplink carrier, the first reference subframe is a subframeassumed by the UE to transmit a PUSCH containing the PHR, for example, asubframe X milliseconds after receiving the first scheduling signalingfor the uplink carrier. For example, if the UE receives the firstscheduling signaling in a subframe n, the first reference subframe isn+4.

It is to be noted that, the PHR report is an MAC layer signaling; and ittakes a certain processing time for the UE to generate the correspondingMAC layer signaling, then contain the corresponding MAC layer signalingin a corresponding MAC PDU, and then bear the corresponding MAC PDU by aphysical layer PUSCH channel. It is assumed that the shortest processingtime is Δm. When the PHR is transmitted on an uplink carrier of atwo-step scheduled unlicensed frequency band, since the time delay fromthe second scheduling signaling to the first reference subframe isshort, often less than Δm, and is thus insufficient to prepare the PHRreport by the UE, in this case, the UE cannot select such a carrier. Forexample, the moment when the PHR report conditions are satisfied is t′,and the UE receives a first scheduling signaling for an uplink carrierCC1 at moment t′−1 ms and a first scheduling signaling for an uplinkcarrier CC2 at a moment t′. The UE receives a second schedulingsignaling for the uplink carrier CC1 at moment t′+1 ms to trigger totransmit a PUSCH at moment t′+3 ms, and the UE receives a secondscheduling signaling for the uplink carrier CC2 at moment t′+2 ms totrigger to transmit a PUSCH at moment t′+5 ms. If it is assumed that ittakes at least Δm=4 ms for the UE to generate and transmit a PHR report,the UE can only select the uplink carrier CC2 to transmit the PHR, andthe first reference subframe is the subframe t′+5.

It is to be noted that the moment t′ when the PHR report conditions aresatisfied and the moment when the UE selects an uplink carrier and anuplink subframe for reporting the PHR are not limited to be the same. Itis possible that the UE selects, at a certain moment after the PHRreport conditions are satisfied, an uplink carrier and an uplinksubframe for reporting the PHR, and then starts preparing the PHR. Forexample, if the moment when the PHR report conditions are satisfied ist′, the UE receives a scheduling signaling from PCell at moment t′+2 msand it is assumed that it takes 1 ms for the UE to decode the schedulingsignaling, the moment when the UE selects an uplink carrier and anuplink subframe for reporting the PHR is t′+3 ms.

Step 802: according to uplink scheduling information received in orbefore a second reference subframe, PHR contents of each uplink carrierto be reported in the first reference subframe are determined, and acorresponding PHR value is determined according to the PHR contents.

Preferably, the second reference subframe is not prior to the subframesatisfying the PHR triggering conditions. Moreover, the second referencesubframe is before the first reference subframe, and the time intervalbetween the second reference subframe and the first reference subframeis no shorter than or equal to the minimum processing time Δm requiredfor the UE to generate the PHR, for example, Δm=4. It can be understoodthat the second reference subframe is a subframe in which the UE startspreparing the PHR report.

Preferably, a method for determining the second reference subframe canbe subdivided into the following.

If the UE selects to transmit the PHR on an uplink carrier scheduled byone-step scheduling, and the base station transmits UL grant at momentt₀ which schedules the UE to transmit a PUSCH at moment t₂ (the firstreference subframe), the second reference subframe in which the UEstarts preparing the PHR report is a subframe in which the UE hasreceived the UL grant. More specifically, the second reference subframeis a subframe in which the UE has decoded received the UL grant, forexample a subframe following the subframe in which the UL grant isreceived. In the one-step scheduling, (t₂−t₀) can be a fixed value, forexample, 4 ms or a fixed value related to Time Division Duplexing (TDD)configuration; or, (t₂−t₀) can also be a variable. For example, thevalue of (t₂−t₀) is dynamically indicated by the UL grant. Or, thesecond reference subframe t₀ in which the UE starts preparing the PHRreport is a subframe when an MAC layer starts generating a PHR MAC CE,or a subframe when a physical layer starts calculating the PHR value.(t₂−t₀) can be a fixed value.

Preferably, if the UE selects to transmit the PHR on an uplink carrierscheduled by two-step scheduling, the base station transmits a firstscheduling signaling UL grant schedules the uplink carrier at moment t₀and the base station transmits a second scheduling signaling at momentt₁ to trigger the UE to transmit a PUSCH on the uplink carrier at momentt₂, the second reference subframe is a subframe in which the UE receivesthe first scheduling signaling UL grant or a subframe on which the UEdecodes the first scheduling signaling UL grant, where the moment t₀ isnot prior to the moment t′ when the PHR report conditions are satisfied;and/or, the second reference subframe is the moment t′ when the PHRreport conditions are satisfied, where the moment t₀ is not later thanthe moment t′ when the PHR report conditions are satisfied, and (t₂-t′)is not less than Δm; and/or, the second reference subframe is a subframeX following the subframe on which the UE receives the first schedulingsignaling UL grant, where the moment t₀ is not prior to the moment t′when the PHR report conditions are satisfied, and X is not less than Δm;and/or, the second reference subframe is a subframe when an MAC layerstarts generating a PHR MAC CE, or a subframe when a physical layerstarts calculating the PHR value. It is to be noted that, since the basestation does not know the moment t′, the base station is unable to knowthe second reference subframe. Despite this, the UE will report whetherthe PHR type is a real value or a virtual value when reporting the PHR,so the understanding of the base station to the PHR will not beinfluenced.

Preferably, the determining PHR contents of each uplink carriercomprises: determining whether the PHR type is a real PHR or a virtualPHR. And, a PHR value is calculated according to the determined type.Wherein, the UE can determine the PHR type of each uplink carrier by oneof the following two ways.

Way 1: For an uplink carrier which can be determined in or before thesecond reference subframe to transmit a PUSCH in the first referencesubframe, the PHR type of the uplink carrier is a real PH. The PHR isdetermined according to the resource allocation information and/orClosed-loop Power Control (TPC) information indicated by the receivedscheduling signaling. In other words, the PHR of the PUSCH is calculatedaccording to the formula of type 1 of “if the UE transmits a PUSCH onlybut does not transmit a PUCCH in a subframe i of a carrier c” in TS36.213.5.1, for example:

PH _(type1,c)(i)={tilde over (P)} _(CMAX,c)(i)−{10 log₁₀(M_(PUSCH,c)(i))+P _(O) _(_) _(PUSCH,c)(j)+α_(c)(j)·PL _(c)+Δ_(TF,c)(i)+f_(c)(i)}

Or, the PHR of the PUSCH is calculated according to the formula of type1 of “if the UE transmits both a PUSCH and a PUCCH in a subframe i of acarrier c”, for example,

PH _(type1,c)(i)={tilde over (P)} _(CMAX,c)(i)−{10 log₁₀(M_(PUSCH,c)(i))+P _(O) _(_) _(PUSCH,c)(j)+α_(c)(j)·PL _(c)+Δ_(TF,c)(i)+f_(c)(i)}

Wherein, the definitions of the parameters in the formulae refer to5.1.1.1/5.1.1.2 in 36.213 of the 3GPP specification.

For convenience of description, in this embodiment, they arecollectively called calculation of the PHR of the PUSCH, regardless ofwhether to simultaneously transmit a PUCCH. Moreover, in the 3GPPspecification, it is also possible to calculate and report the PHR oftype 2. This embodiment is applicable to the PHR of type 1, and is alsoapplicable to the PHR of type 2. For convenience of description, theyare collectively called calculation of the PHR of the PUSCH.

However, for an uplink carrier which has not been determined in orbefore the second reference subframe to transmit a PUSCH in the firstreference subframe, the UE determines the PHR type of the uplink carrieras a virtual PHR. The PHR is calculated according to a predefinedreference format, i.e., according to the PHR formula of type 1 “if theUE does not transmit a PUSCH” in TS 36.213.5.1, for example,

PH _(type1,c)(i)={tilde over (P)} _(CMAX,c)(i)−{P _(O) _(_)_(PUSCH,c)(1)+α_(c)(1)·PL _(c) +f _(c)(i)}

Wherein, the definitions of the parameters in the formulae refer to5.1.1.1/5.1.1.2 in 36.213 of the 3GPP specification.

This embodiment is applicable to the PHR of type 1, and is alsoapplicable to the PHR of type 2. For convenience of description, theyare collectively called calculation of the PHR of the PUSCH.

Preferably, if {tilde over (P)}_(CMAX,c)(i) is related to whether othercarriers transmit a PUSCH, and/or whether other carriers transmit aPUCCH, when calculating {tilde over (P)}_(CMAX,c)(i), it is assumed thatthe uplink carrier which has been determined in the second referencesubframe to transmit a PUSCH in the first reference subframe is atransmitting uplink carrier, and the uplink carrier which has not beendetermined in the second reference subframe to transmit a PUSCH in thefirst reference subframe is a non-transmitting uplink carrier.

Here, for convenience of description, for the uplink transmission on anunlicensed frequency band carrier, regardless of whether the UE passesClear Channel Assessment (CCA) detection (access the unlicensedfrequency band carrier), only if the received scheduling/triggersignaling indicates the transmission in the first reference subframe, itis assumed that the UE performs a PUSCH transmission in the firstsubframe, when calculating the PHR. Of course, based on the LBTmechanism, if the UE fails to pass the CCA detection, the UE will nottransmit a PUSCH in the first reference subframe.

Preferably, when calculating the PHR of an uplink carrier scheduled byone-step scheduling, the UE can determine the PHR type of thecorresponding uplink carrier according to whether the UL grant signalingfor scheduling transmission in the first reference subframe has beenreceived in or before the second reference subframe. In other words, ifthe UE has not received until the second reference subframe, the ULgrant scheduling the transmission in the first reference subframe, theUE is absolutely impossible to transmit a PUSCH in the first referencesubframe, so that the PHR of the corresponding uplink carrier is avirtual PHR. If the UE has received, in or before the second referencesubframe, the UL grant for scheduling transmission in the firstreference subframe, the PHR of the corresponding uplink carrier is areal PHR.

Preferably, when calculating the PHR of an uplink carrier scheduled bytwo-step scheduling, if the UE has received a second schedulingsignaling in or before the second reference subframe, the UE candetermine the PHR type of the corresponding uplink carrier according towhether the uplink transmission triggered by the second schedulingsignaling is located in the first reference subframe. In other words, ifthe UE has received the second scheduling signaling in or before thesecond reference subframe which triggers uplink transmission, and thetriggered uplink transmission is not to be transmitted in the firstreference subframe, the UE is absolutely impossible to transmit a PUSCHin the first reference subframe, and the PHR of the correspondingcarrier is a virtual PHR; and, if the UE has received the secondscheduling signaling in or before the second reference subframe whichtriggers uplink transmission, and the triggered uplink transmission isto be transmitted in the first reference subframe, the PHR of thecorresponding carrier is a real PHR, even in a case eventually UE doesnot transmit an uplink in the first reference subframe, such as the UEpossibly fails to pass the CCA detection and does not transmit an uplinkin the first reference subframe.

Preferably, when calculating the PHR of an uplink carrier scheduled bytwo-step scheduling, if the UE has not received the second schedulingsignaling in or before the second reference subframe or not received thefirst scheduling signaling, the PHR of the corresponding uplink carrieris a virtual PHR, regardless of whether the UE eventually transmits anuplink signal in the first reference subframe.

Preferably, if the UE selects to transmit the PHR on a two-stepscheduled PUSCH, the PHR of the uplink carrier of the PUSCH is a realPHR which is calculated according to the received first schedulingsignaling.

In a specific application scenario, the base station configures threeuplink carriers for the UE, where the CC1 is a licensed frequency bandcarrier, and the CC2 and the CC3 are unlicensed frequency band carriers.After the PHR triggering conditions are satisfied, the UE selects toreport the PHR on the CC1, and the first reference subframe is t₃. Inother words, the base station schedules the UE to transmit a PUSCH inthe first reference subframe t₃ on the CC1, and the UE will include thePHR report in the PUSCH. The second reference subframe is moment t,where t is prior to t₃. It is assumed that the CC1 and the CC2 isscheduled by one-step scheduling while the CC3 is scheduled by two-stepscheduling. When it is assumed that the UE has received, in the secondreference subframe t, uplink scheduling signaling for the CC1 and CC2,and the UE has received a first scheduling signaling for the CC3 but notreceived a second scheduling signaling for the CC3. Then, the UEcalculates real PHRs of the CC1 and CC2 according to the receivedscheduling signaling, and calculates a virtual PHR of the CC3 accordingto the predefined reference format, as shown in FIG. 9.

In another specific application scenario, it is assumed that the UE hasreceived, in the second reference subframe t, uplink schedulingsignalings for the CC1 and CC2, the UE has received the first schedulingsignaling for the CC3 and the second scheduling signaling for the CC3,and the uplink transmission time triggered by the second schedulingsignaling is a subframe t₂, where t₂ is not equal to the first referencesubframe t₃. Hence, the UE calculates real PHRs of the CC1 and CC2according to the received scheduling signaling, and calculates a virtualPHR of the CC3 according to the predefined reference format, as shown inFIG. 10.

In still another specific application scenario, it is assumed that theUE has received, in the second reference subframe t, uplink schedulingsignalings for the CC1 and CC2, and the UE has received a firstscheduling signaling for the CC3 and a second scheduling signaling ofthe CC3, the uplink transmission time triggered by the second schedulingsignaling is a subframe t₂, where t₂ is equal to the first referencesubframe t₃. Hence, the UE separately calculates real PHRs of the CC1,CC2 and CC3 according to the received scheduling signaling, as shown inFIG. 11.

In yet another specific application scenario, it is assumed that the UEhas received, in the second reference subframe t, an uplink schedulingsignaling for the CC1, and the UE has received a first schedulingsignaling for the CC3, but not received a second scheduling signalingfor the CC3 and an uplink scheduling signaling for the CC2. Hence, theUE calculates a real PHR of the CC1 according to the received schedulingsignaling, and calculates virtual PHRs of the CC2 and CC3 according tothe predefined reference format, as shown in FIG. 12.

Way 2: For an uplink carrier which can be determined in the secondreference subframe to not transmit a PUSCH in the first referencesubframe, the PHR type of the uplink carrier is a virtual PHR; however,for an uplink carrier which can be determined in the second referencesubframe to transmit a PUSCH in the first reference subframe or for anuplink carrier which possibly transmits a PUSCH in the first referencesubframe, the PHR type of the uplink carrier is a real PHR.

Preferably, if {tilde over (P)}_(CMAX,c)(i) is related to whether othercarriers transmit a PUSCH, it is assumed when calculating {tilde over(P)}_(CMAX,c)(i) that the uplink carrier which can be determined in thesecond reference subframe to transmit a PUSCH in the first referencesubframe or the uplink carrier which possibly transmits a PUSCH in thefirst reference subframe is a transmitting uplink carrier.

Preferably, when calculating the PHR of an uplink carrier scheduled byone-step scheduling, the UE can determine the PHR type of thecorresponding uplink carrier according to whether the UL grant signalingfor scheduling transmission in the first reference subframe has beenreceived in the second reference subframe. In other words, if the UE hasnot received the UL grant scheduling the transmission in the firstreference subframe until the second reference subframe, the UE isabsolutely impossible to transmit a PUSCH in the first referencesubframe, so that the PHR of the corresponding uplink carrier is avirtual PHR. If the UE has received, in or before the second referencesubframe, the UL grant for scheduling transmission in the firstreference subframe, the PHR of the corresponding uplink carrier is areal PHR.

Preferably, when calculating the PHR of an uplink carrier scheduled bytwo-step scheduling, if the UE has received a second schedulingsignaling in or before the second reference subframe, the UE candetermine the PHR type of the corresponding uplink carrier according towhether the uplink transmission triggered by the second schedulingsignaling is located in the first reference subframe. In other words, ifthe UE has received the second scheduling signaling in or before thesecond reference subframe and then triggers uplink transmission, and thetriggered transmission moment of the uplink transmission is not thefirst reference subframe, the UE is absolutely impossible to transmit aPUSCH in the first reference subframe, and the PHR of the correspondingcarrier is a virtual PHR; and, if the UE has received the secondscheduling signaling in or before the second reference subframe and thentriggers uplink transmission, and the triggered transmission moment ofthe uplink transmission is the first reference subframe, the PHR of thecorresponding carrier is a real PHR, even in a case where the UEpossibly fails to pass the CCA detection and does not transmit an uplinkin the first reference subframe eventually.

Preferably, when calculating the PHR of an uplink carrier scheduled bytwo-step scheduling, if the UE has received the first schedulingsignaling but not received the second scheduling signaling in the secondreference subframe, the UE can determine the PHR type of thecorresponding uplink carrier according to the first schedulingsignaling. For example, if the received first scheduling signaling canindicate that the uplink transmission is absolutely impossible to beperformed in the first reference subframe, or if the second referencesubframe is out of a valid time window of the first schedulingsignaling, the PHR type of the corresponding uplink carrier is a virtualPHR. And/or, if the UE is unable to exclude the possibility ofperforming uplink transmission in the first reference subframe by usingthe received first scheduling signaling, for example, the firstscheduling signaling does not contain information related to thetransmission time or the contained information related to thetransmission time cannot exclude the possibility of performing uplinktransmission in the first reference subframe, the PHR type of thecorresponding uplink carrier is a real PHR, regardless of whether the UEeventually performs uplink transmission in the first reference subframe.

Preferably, when calculating the PHR of an uplink carrier scheduled bytwo-step scheduling, if the UE is unable to exclude the possibility ofperforming uplink transmission in the first reference subframe by usingthe received first scheduling signaling, even though the UE can excludethe possibility of performing uplink transmission in the first referencesubframe by using the subsequently received second scheduling signaling,the PHR type of the corresponding uplink carrier as a real PHR,regardless of whether the UE eventually performs uplink transmission inthe first reference subframe.

Preferably, when calculating the PHR of an uplink carrier scheduled bytwo-step scheduling, if the UE has not received the first schedulingsignaling in or before the second reference subframe, the PHR type ofthe corresponding uplink carrier is a virtual PHR.

Preferably, if the UE has received more than one first schedulingsignaling in or before the second reference subframe, and/or the UE hasreceived a first scheduling signaling for two-step scheduling and asignaling for one-step scheduling, the UE can determine the PHR of thecorresponding uplink carrier by one or more of the following methods.

(1) If the UE has received a signaling for two-step scheduling and asignaling for one-step scheduling in the second reference subframe orbefore the second reference subframe, the UE determines the PHR type ofthe corresponding uplink carrier according to the result of the one-stepscheduling.

(2) If the UE has received a signaling for two-step scheduling signalingand a signaling for one-step scheduling in the second reference subframeor before the second reference subframe, and if the signaling forone-step scheduling schedules the uplink transmission of a firstsubframe, a real PHR is calculated according to the one-step schedulingsignaling; if the signaling for one-step scheduling does not schedulethe uplink transmission of the first uplink subframe but the UE hasreceived a first scheduling signaling for two-step scheduling, and thefirst reference subframe is within a valid time window of the firstscheduling signaling, or the first reference subframe is within a time Xms after the valid time window of the first scheduling signaling (forexample, X=1 ms, i.e., within 1 ms after the valid time window), the UEcalculates a real PHR according to the first scheduling signaling. Ifthe UE has received a multiple of first scheduling signalings, one ofthe first scheduling signalings can be selected in accordance with theway (3) so as to determine the real PHR.

(3) If the UE has received a multiple of first scheduling signalings inor before the second reference subframe, and the UE has not receivedsecond scheduling signalings corresponding to the first schedulingsignalings, within the valid time window of the first schedulingsignalings, the PHR type of the corresponding uplink carrier is a realPHR. Meanwhile, the UE selects, according to a predefined rule, onefirst scheduling signaling and then determines a real PHR, for example:

-   -   selecting the first one of the received first scheduling        signalings as a reference, and calculating a real PHR, or,    -   selecting the last one of the received first scheduling        signalings as a reference, and calculating a real PHR, or,    -   if all the first scheduling signalings are received in a same        subframe, selecting a first scheduling signaling with a lowest        PDCCH/EPDCCH search space index number as a reference, and        calculating a real PHR.

Preferably, if the UE selects to transmit the PHR on a two-stepscheduled PUSCH, the PHR of the uplink carrier of the PUSCH iscalculated as a real PHR according to the received first schedulingsignaling.

In a specific application scenario, the base station configures threeuplink carriers for the UE, where the CC1 is a licensed frequency-bandcarrier, and the CC2 and the CC3 are unlicensed frequency band carriers.After the PHR triggering conditions are satisfied, the UE selects toreport the PHR on the CC1, and the first reference subframe is t₃. Inother words, the base station schedules the UE to transmit a PUSCH onthe CC1 in the first reference subframe t₃, and the UE will contain thePHR report in the PUSCH. The second reference subframe is moment t,where t is prior to t₃. It is assumed that the CC1 and the CC2 isscheduled by one-step scheduling while the CC3 is scheduled by two-stepscheduling. It is assumed that the UE has received, in or before thesecond reference subframe t, uplink scheduling signaling for the CC1 andCC2, and the UE has received a first scheduling signaling for the CC3but not received a second scheduling signaling for the CC3. Then, the UEseparately calculates real PHRs of the CC1, CC2 and CC3 according to thereceived scheduling signalings, as shown in FIG. 13.

In another specific application scenario, it is assumed that the UE hasreceived, in the second reference subframe t, uplink schedulingsignalings for the CC1 and CC2, and the UE has received a firstscheduling signaling for the CC3 but not received a second schedulingsignaling for the CC3, wherein the first scheduling signaling containsindication information about the transmission time which is delayed 6 mswith respect to the moment of the second scheduling signaling. If it isassumed that a time interval between the second reference subframe t andthe first reference subframe t₃ is 5 ms, although the UE has notreceived the second scheduling signaling for the CC3 and thus cannotdetermine the uplink transmission time of the CC3, the UE can decidethat the uplink transmission of the CC3 is absolutely later than thefirst reference subframe t₃. Even if the UE receives the secondscheduling signaling as early as moment t+1, the triggered uplinktransmission is also performed at t+1+6 ms. Hence, the UE separatelycalculates real PHRs of the CC1 and CC2 according to the receivedscheduling signalings, and calculates a virtual PHR of the CC3 accordingto the predefined format.

In still another specific application scenario, after the PHR triggeringconditions are satisfied, the UE selects to report the PHR on the CC1,and the first reference subframe is t₃. In other words, the base stationschedules the UE to transmit a PUSCH on the CC1 on the first referencesubframe t₃, and the UE will contain the PHR report in the PUSCH. Thesecond reference subframe is moment t, where t is prior to t₃. It isassumed that the CC1 is scheduled by one-step scheduling while the CC2and CC3 is scheduled by two-step scheduling. It is assumed that the UEhas received, in the second reference subframe t, an uplink schedulingsignaling for the CC1, and the UE has received a first schedulingsignaling for the CC3 but not received a second scheduling signaling forthe CC3. Then, the UE calculates real PHRs of the CC1 and CC3 accordingto the received scheduling signalings, and calculates a virtual PHR ofthe CC2 according to the predefined format, as shown in FIG. 14.

In yet another specific application scenario, After the PHR triggeringconditions are satisfied, the UE receives, in the second referencesubframe, a one-step scheduling signaling UL grant for the CC1, the UEdecides to report the PHR on the CC1, and the first reference subframeis t₃. In other words, the base station schedules the UE to transmit aPUSCH on the CC1 in the first reference subframe 6, and the UE willcontain the PHR report in the PUSCH. On the CC2, the UE has notreceived, before the second reference subframe, a non-triggered firstscheduling signaling for two-step scheduling or a UL grant for one-stepscheduling, and the UE has received the first scheduling signaling afterthe second reference subframe. On the CC3, the UE has received a firstscheduling signaling 1 (not triggered) before the second referencesubframe, and has received another first scheduling signaling 2 (nottriggered) in the second reference subframe; and, the first referencesubframe is within the valid time of the two first schedulingsignalings. Then, the UE calculates real PHRs of the CC1 and CC3according to the received scheduling signalings, and calculates avirtual PHR of the CC2 according to the predefined reference format.Wherein, the real PHR of the CC3 is calculated according to the firstscheduling signaling 1, as shown in FIG. 15.

It is to be noted that majority of the examples described herein showthe transmission of the PHR on a licensed frequency band carrier, butthey are also applicable to the transmission of the PHR on an unlicensedfrequency band carrier. As described in the background art, inaccordance with the existing standards, the UE can selectively transmita PHR on a proper carrier.

If the PHR is transmitted on an unlicensed frequency band carrier and ifthe two-step scheduling is adopted, a time interval between the secondscheduling signaling and the uplink transmission (containing the PHR) isgenerally not less than the minimum processing time delay of the uplinktransmission. For example, if the PHR triggering conditions aresatisfied at a subframe n, the UE receives a second scheduling signalingafter the subframe n (a subframe m) and the PUSCH transmission triggeredby the second scheduling signaling is performed in a subframe m+4 orafter the subframe m+4, the UE can transmit PUSCH+PHR on this uplinkcarrier. For another example, if the second scheduling signaling hasbeen received before the subframe n (a subframe l), but the PUSCHtransmission triggered by the second scheduling signaling is performedin a subframe n+4 or after the subframe n+4, the UE can transmitPUSCH+PHR on this uplink carrier.

As shown in FIG. 16, the CC1 is a licensed frequency band carrier (byone-step scheduling). After the PHR triggering conditions are satisfied,the UE receives, in or before the second reference subframe, secondscheduling signalings for the CC2 and CC3 for separately scheduling totransmit PUSCHs in a subframe p and a subframe q. A time intervalbetween the subframe p and the second reference subframe is 4 ms, and atime interval between the subframe q and the second reference subframeis 6 ms. The UE selects to report the PHR on the CC2, the firstreference subframe is t₃ (i.e., the subframe p), and the UE contains thePHR report in the PUSCH. When in or before the second referencesubframe, the UE has not received a scheduling signaling for the CC1.The PHR of the CC1 is a virtual PHR. The PHR of the CC2 is a real PHR.Although the UE has received the first scheduling signaling for the CC3before the second reference subframe, the PHR of the CC3 is a virtualPHR because the PUSCH transmission indicated by the second schedulingsignaling received in the second reference subframe is not performed inthe first reference subframe.

As another implementation, if the PHR is transmitted on an unlicensedfrequency band carrier and if the two-step scheduling is adopted, thesecond reference subframe is generally a subframe after the UE hasreceived a first scheduling signaling for scheduling the unlicensedfrequency band carrier, and can be prior to a subframe of the secondscheduling signaling. As described above, a time interval between thefirst scheduling signaling and the uplink transmission (containing thePHR) is not less than the minimum processing time delay of the uplinktransmission. Therefore, the UE can have enough time to generate a PHRand a PUSCH. However, it is to be noted that, once the UE has generatedthe PHR, the UE will not change the PHR value even if the time intervalbetween the subsequently received second scheduling signaling and theuplink transmission (containing the PHR) is not less than the minimumprocessing time delay of the uplink transmission.

As shown in FIG. 21, the CC1 is a licensed frequency band carrier (byone-step scheduling). After the PHR triggering conditions are satisfiedin a subframe n−1, the UE receives, in a subframe n, a first schedulingsignaling for the CC2, and the UE determines to transmit a PUSCH on theCC2. Hence, the second reference subframe is the subframe n, and thefirst reference subframe is a subframe n+x, where it is assumed thatx=4. The UE starts generating an MAC packet and a PHR in the secondreference subframe. Moreover, the UE receives a first schedulingsignaling for the CC3 in a subframe n−2, a second scheduling signalingin a subframe n+1 for scheduling a PUSCH in a subframe n+2, and aone-scheduling signaling for the CC1 in the subframe n+2 for schedulingPUSCH transmission in a subframe n+6. Then, the PHR of the carrier CC2transmitting the PHR is a real PHR. Since the CC1 adopting the one-stepscheduling does not transmit a PUSCH in the first reference subframen+4, the PHR of the CC1 is a virtual PHR. Since the CC3 by the two-stepscheduling has received the first scheduling signaling in or before thesecond reference subframe and the first reference subframe n+4 is withinthe valid time of the first scheduling signaling, the PHR of the CC3 isa real PHR. Eventually, the UE receives a second scheduling signalingfor the CC2 in a subframe n+5 for scheduling transmission of a PUSCH anda PHR in a subframe n+6. It is not hard to see that, although thelicensed carrier CC1 transmits a PUSCH in the subframe n+6, the PHRreported by the UE is a virtual PHR; however, the unlicensed CC3transmits a PUSCH in the subframe n+6, but the PHR reported by the UE isa real PHR.

It is to be noted that, the above description is illustrated by takingthe PHR of a PUSCH as example, but the above ways are also applicable tothe PHR of a PUCCH or the PHR of a PUSCH needing to take the influenceof the PUCCH into consideration. For example, the calculation of the PHRof type 1 or the PHR of type 2 in the TS 36.213 5.1.1.2 is also relatedto whether the UE will transmit a PUCCH in a subframe i. Since thetransmission of a downlink subframe is likely to occur on a multiple ofcarriers with different TTI lengths, and a time delay from the receiptof downlink data PDSCH by the UE to the report of an ACK/NACK in a PUCCHby the UE changes with different lengths, it is possible that the UEdoes not determine in the second reference subframe whether a PUCCH isto be transmitted in the first reference subframe. Then, the UE canassume whether to transmit a PUCCH in accordance with Way 1 or Way 2 inthe step 802, so as to calculate a corresponding PHR. For example, ifthe UE does not determine in the second reference subframe whether aPUCCH is to be transmitted in the first reference subframe, then for anuplink carrier possibly transmitting the PUCCH, for example, Pcell, thevalue of the PHR is calculated on the assumption that the PUCCH is notto be transmitted. For example:

${{PH}_{{type}\; 2}(i)} = {{P_{{CMAX},c}(i)} - {{\quad\quad}10\mspace{14mu} {\quad{\log_{10}\left( \begin{matrix}{10^{{({{{10{\log_{10}{({M_{{PUSCH},c}{(i)}})}}} + {P_{O}\mspace{14mu} {PUSCH}}},{{c{(j)}} + {{\alpha_{c}{(j)}} \cdot {PL}_{c}} + {\Delta_{{TF},c}{(i)}} + {f_{c}{(i)}}}})}/10} +} \\10^{{({P_{0{\_ PUSCH}} + {PL}_{c} + {g{(i)}}})}/10}\end{matrix} \right)}}}}$

and for an uplink carrier not transmitting the PUCCH, for example,Scell, the value of the PHR is calculated on the assumption that thePUCCH is not to be transmitted. For example:

PH _(type1,c)(i)={tilde over (P)} _(CMAX,c)(i)−{10 log₁₀(M_(PUSCH,c)(i))+P _(O) _(_) _(PUSCH,c)(j)+α_(c)(j)·PL _(c)+Δ_(TF,c)(i)+f_(c)(i)}

It is to be noted that, if, in the step 801, the UE can only select totransmit a PUSCH on an one-step scheduled PUSCH, although majority ofthe examples described herein show the transmission of the PHR on alicensed frequency band carrier, and are also applicable to thetransmission of the PHR on an one-step scheduled unlicensed frequencyband carrier, it is unable to transmit the PHR on a two-step scheduledunlicensed frequency band carrier.

Way 3: For a carrier by two-step scheduling, the PHR type of the uplinkcarrier is a virtual PHR. In other words, regardless of whether the UEhas received a first scheduling signaling and/or a second schedulingsignaling in the first reference subframe, the UE reports a virtual PHR.

The UE only needs to, when generating a PHR report, for example, in thesecond reference subframe, decide that the uplink carrier is an uplinkcarrier by two-step scheduling. Then, the UE generates a virtual PHR ofthe corresponding carrier. For example, if in or before the secondreference subframe, a first scheduling signaling has been received, buta signaling for one-step scheduling has not been received, the UEgenerates a virtual PHR of the corresponding carrier.

Further, if the UE decides in the second reference subframe that theuplink carrier adopts both the two-step scheduling and the one-stepscheduling, the UE determines the PHR type according to the schedulinginformation about the one-step scheduling. For example, the UE hasreceived two pieces of scheduling information in the second referencesubframe, where one piece of scheduling information is a firstscheduling signaling for two-step scheduling while the other piece ofscheduling information is a scheduling signaling for one-stepscheduling, and the uplink subframes scheduled by the two schedulingsignalings are different. Wherein, if the scheduling signaling forone-step scheduling schedules the uplink transmission in the firstreference subframe, the UE reports a real PHR regardless of the contentsindicated by the two-step scheduling signaling; and, if the schedulingsignaling for one-step scheduling schedules uplink transmission not inthe first reference subframe, the UE reports a virtual PHR regardless ofthe contents indicated by the two-step scheduling signaling.

Further, if the UE has received neither the first scheduling signalingfor two-step scheduling nor the scheduling signaling for one-stepscheduling when generating the PHR report, the UE reports a virtual PHR.

It is not hard to see that, in Way 3, for a carrier to report the PHR,only when the UE receives a scheduling signaling for one-step schedulingwhich indicates to transmit an uplink signal in the first referencesubframe, the UE generates a real PHR report; and, in other cases, theUE generates a virtual PHR report.

The PHR information provided for the base station in Way 3 is lesseffective than that provided in Way 1 and Way 2, but Way 3 is relativelysimple.

Preferably, if the UE selects to transmit the PHR on a two-stepscheduled PUSCH, the PHR of the uplink carrier of the PUSCH iscalculated as a real PHR according to the received first schedulingsignaling.

Preferably, if the UE selects to transmit the PHR on a two-stepscheduled PUSCH, the PHR of the uplink carrier of the PUSCH iscalculated as a virtual PHR.

Step 803: The UE generates a PHR of each uplink carrier according to thedetermined PHR value of each uplink carrier, and reports the generatedPHR of each uplink carrier on the selected uplink carrier and in theselected first reference subframe.

Preferably, the UE can generate a PHR report of an MAC layer inaccordance with the prior art and according to the PHR value calculatedby the physical layer, and then transmit in the first reference subframeby the selected PUSCH of uplink carrier.

Preferably, if the UE selects to transmit the PHR on a two-stepscheduled PUSCH, the UE can generate a PHR report of an MAC layer inaccordance with the prior art and according to the PHR value calculatedby the physical layer assuming a first reference subframe, and thentransmit, in a subframe indicated by a second scheduling signaling, bythe selected PUSCH of uplink carrier upon receiving the secondscheduling signaling. In this case, a subframe eventually transmittingthe PUSCH and the first reference subframe for calculating the PHR canbe different subframes. However, for convenience of description, bothare called as first reference subframes in the present invention.

Like the prior art, the PHR contains not only a PHR value, but also anindication of a real PHR or a virtual PHR, and/or a value of the maximumpower Pcmax,c of the carrier.

In the present invention, clocks of the uplink carriers can be notaligned completely. For example, in the Carrier Aggregation (CA), it issupported that a difference in the advance amount of uplink transmissiontime of the UE on each aggregated uplink carrier is about 30 us. Withinthis time interval, it can be considered that the same subframes can beprocessed by the UE even if the subframes are later in time on somecarriers.

Embodiment 3

In this embodiment, the basic steps are the same as Embodiment 2, i.e.,the steps 801, 802 and 803. However, the specific way of selecting acarrier to transmit the PHR in the step 801 and the specific way ofgenerating a PHR report of each carrier by the UE in the step 802 aredifferent. Specifically:

If there are at least two carriers among a multiple of aggregatedcarriers, and when the minimum time delay from the receipt of an uplinkscheduling signaling by the UE to the transmission of the scheduleduplink signal by the UE is different, and/or when the time slot duration(or called as the scheduled time unit TTI length) is different, whencalculating a PHR of a corresponding subframe, the UE can calculate thePHR by one or more of the following four ways.

Way 1: When the UE selects to transmit PHRs on an uplink carrier with alonger TTI length, PHRs of other corresponding carriers with a shorterTTI length within the first reference subframe is calculated based on afirst shorter TTI within the first reference subframe.

In a specific application scenario, the base station configures threeuplink carriers for the UE, where the CC1 carrier has a subframeduration of 1 ms, the CC2 carrier has a subframe duration of 0.5 ms andthe CC3 carrier has a subframe duration of 0.25 ms. After the PHRtriggering conditions are satisfied, the UE selects to report the PHR onthe CC1, and the first reference subframe is t₃ (subframe duration is 1ms). In other words, the base station schedules the UE to transmit aPUSCH on the CC1 in the first reference subframe t₃, and the UE includesPHR reports of the CC1, CC2 and CC3 in the PUSCH. The PHR of the CC2should be determined according to the uplink transmission condition of afirst subframe of the CC2 within an uplink subframe L1 of the CC1, i.e.,a subframe n1 of the CC2. The PHR of the CC3 should be determinedaccording to the uplink transmission condition of a subframe m1 of theCC3. For example, if the UE transmits a PUSCH in a subframe n1 of theCC2, the PHR of the CC2 is a real PHR; and, if the subframe n1 of theCC2 is a downlink subframe or does not schedules a PUSCH, the PHR is avirtual PHR. This is applicable to the CC3, as shown in FIG. 17.

It is to be noted that, similar to the step 802 in Embodiment 2, the UEalso decides the PHR of each carrier within the first referencesubframe, according to whether has received a scheduling signaling forscheduling and/or triggering the UE to transmit a PUSCH in the firstreference subframe, and/or the first scheduling signaling, and/or thesecond scheduling signaling has been received in or before the secondreference subframe.

For example, even if each carrier adopts one-step scheduling, theminimum time delay from the receipt of the scheduling signaling by theUE to the transmission of the PUSCH by the UE may be different. For acarrier with a small TTI length, the minimum time delay is also short,as shown in FIG. 18.

It is assumed that the carrier CC1 has a subframe duration of 1 ms, andthe time delay from the scheduling signaling to the PUSCH transmissionis 4 ms; and, the carrier CC2 has a subframe duration of 0.25 ms, andthe time delay from the scheduling signaling to the PUSCH transmissionis 1 ms. Hence, after the PHR triggering conditions are satisfied, theUE selects to report the PHR on the CC1, and the first referencesubframe is t₃. In other words, the base station schedules the UE totransmit a PUSCH on the CC1 in the first reference subframe t₃, and theUE includes PHR reports of the CC1 and CC2 in the PUSCH. In the secondreference subframe t (after the PHR triggering conditions aresatisfied), the UE starts preparing PHR reports of the CC1 and CC2.Since the UE has not received the scheduling signaling for the CC2 onthe second reference subframe moment t, the UE calculates the PHR of theCC2 in accordance with the virtual PHR even if the UE has subsequentlyreceived the scheduling signaling for the CC2 for scheduling the UE totransmit a PUSCH in a subframe m1 of the CC2.

Like the prior art, the PHR contains not only a PHR value, but also anindication of a real PHR or a virtual PHR, and/or a value of the maximumpower Pcmax,c of the carrier.

Way 2: When the UE selects to transmit PHRs on an uplink carrier with alonger TTI length, PHRs of other corresponding carriers with a shorterTTI length within the first reference subframe is calculated based onthe first scheduled shorter TTI within the first reference subframe. Ifthere is no shorter subframe is scheduled within the first referencesubframe, reporting a PHR of the first shorter TTI within the firstreference subframe, or reporting a PHR of any shorter TTI within thefirst reference subframe, where the PHR is a virtual PHR.

Preferably, the UE does not need to report an indication of a TTI index.

Preferably, the UE reports not only the PHR but also an indication of aTTI index. Preferably, N bits are added in the PHR signaling to indicateindex indications of N shorter TTIs in the first reference subframe.

For example, the base station configures three uplink carriers for theUE, where the CC1 carrier has a subframe duration of 1 ms, the CC2carrier has a subframe duration of 0.5 ms and the CC3 carrier has asubframe duration of 0.25 ms. After the PHR triggering conditions aresatisfied, the UE selects to report the PHR on the CC1, and the firstreference subframe is t₃. In other words, the base station schedules theUE to transmit a PUSCH on the CC1 on the first reference subframe 6, andthe UE includes PHR reports of the CC1, CC2 and CC3 in the PUSCH. If thebase station schedules the CC2 to transmit a PUSCH in a subframe n1+1,and the UE has received an uplink scheduling signaling for schedulingthe PUSCH transmission on CC2 in subframe n1+1 before preparing the PHR,the UE calculates the PHR of the CC2 in accordance with the subframen1+1. Since the PUSCH transmission has been scheduled, the PHR of theCC2 is a real PHR. This is applicable to the CC3, as shown in FIG. 19.If the UE needs to further report an indication of the subframe index,the PHR of the CC2 needs to indicate a second subframe within the firstreference subframe, and the PHR of the CC3 indicates a second subframewithin the first reference subframe.

It is to be noted that, similar to Embodiment 2, the UE also decides thePHR of each carrier within the first reference subframe, according towhether a scheduling signaling for scheduling and/or triggering the UEto transmit a PUSCH in the first reference subframe, and/or the firstscheduling signaling, and/or the second scheduling signaling has beenreceived in or before the second reference subframe. For example, inFIG. 9, when preparing the PHR, if the UE has not received a schedulingsignaling for scheduling the subframe n1+1 of the carrier CC2 totransmit a PUSCH, the UE reports the PHR of the CC2 as a virtual PHRbased on subframe n1.

Way 3: When the UE selects to transmit PHRs on an uplink carrier with alonger TTI length, PHRs of other corresponding carriers with a shorterTTI length within the first reference subframe is calculated based on ashorter TTI within the first reference subframe, which is up to UEimplementation.

Preferably, the UE does not need to report an indication of a TTI index.

Preferably, the UE reports not only the PHR but also an indication of aTTI index.

For example, the base station configures three uplink carriers for theUE, where the CC1 carrier has a subframe duration of 1 ms, the CC2carrier has a subframe duration of 0.5 ms and the CC3 carrier has asubframe duration of 0.25 ms. After the PHR triggering conditions aresatisfied, the UE selects to report the PHR on the CC1, and the firstreference subframe is t₃. In other words, the base station schedules theUE to transmit a PUSCH on the CC1 on the first reference subframe t₃,and the UE includes PHR reports of the CC1, CC2 and CC3 in the PUSCH.The UE can select to report any one of two subframes of the CC2 withinan uplink subframe L1 of the CC1 to calculate the PHR of the CC2. Forexample, the UE can select the subframe n1+1 to calculate the PHR. Sincethe PUSCH transmission has been scheduled, the PHR is a real PHR. Thisis applicable to the CC3.

Preferably, the UE calculates the PHR by preferentially consideringwhether a subframe has been determined on the second reference subframet to transmit a PUSCH. For example, if, for subframes m1 and m1+1 of theCC3, it has been determined on the second reference subframe t that thesubframe m1 does not transmit a PUSCH and the subframe m+1 transmits aPUSCH, but it has not been determined on the second reference subframe twhether subframes m1+2 and m1+3 transmit a PUSCH, the UE will select oneof the subframes m1 and m1+1 to calculate the PHR.

Preferably, when reporting the PHR value and the PHR type (virtual orreal), the UE will also report the referenced subframe. For example, forthe carrier CC3, two bits can be used to indicate that the reported PHRis which one of the subframes m1 to m1+3.

Way 4: When the UE selects to transmit PHRs on an uplink carrier with ashorter TTI length, PHRs of other corresponding carriers with a longerTTI length overlapping with the first reference subframe should becalculated according to a TTI containing the first reference subframe.The calculation of a PHR of an uplink carrier with a smaller TTI lengthcan be performed in accordance with one of the Ways 1 to 3.

For example, the base station configures three uplink carriers for theUE, where the CC1 carrier has a subframe duration of 1 ms, the CC2carrier has a subframe duration of 0.5 ms and the CC3 carrier has asubframe duration of 0.25 ms. After the PHR triggering conditions aresatisfied, the UE selects to report the PHR on the CC3, and the firstreference subframe is t₃. In other words, the base station schedules theUE to transmit a PUSCH on the CC3 on the first reference subframe t₃(subframe m1+1), and the UE includes PHR reports of the CC1, CC2 and CC3in the PUSCH. On the CC1, no uplink transmission is scheduled in asubframe L1 containing the subframe m1+1 of the CC3, so the PHR is avirtual PHR. On the CC2, no uplink transmission is scheduled in asubframe n1 containing the subframe m1+1 of the CC3, so the PHR is avirtual PHR. The PHR of the CC3 is a real PHR, as shown in FIG. 20.

In this embodiment, it is assumed that the UE has determined the TTIlength of each carrier of the first reference subframe before the secondreference subframe t. For example, the change in TTI length isconfigured semi-statically. On the other hand, if the UE is unable todetermine the TTI length of each carrier within the first referencesubframe before the second reference subframe t, for example, if the TTIlength of some carriers changes dynamically and the UE has not receivedany information indicative of the TTI length before the second referencesubframe t, the UE calculates a virtual PHR according to the predefinedreference TTI length.

Embodiments 2 and 3 of the present invention have been described mainlywith respect to a Carrier Aggregation (CA) scenario. The UE reports PHRsof all activated uplink carriers. The present invention is alsoapplicable to a dual-connectivity scenario. The UE reports, to each eNB,PHRs of all activated uplink carriers under this eNB, and PHRs of allactivated uplink carriers under another eNB. The PHRs of the another eNBcan be always reported as virtual PHRs in accordance with thehigher-layer configuration; or the PHRs are reported according to thescheduling condition and in accordance with the higher-layerconfiguration. In this case, the calculation and reporting of the PHRscan be performed according to the methods provided by the presentinvention.

Further, the base station can also group the activated uplink carriersof the UE. For example, uplink carriers with a longer TTI and uplinkcarriers with a shorter TTI are classified into two groups. Each groupreports PHRs in this group, and for the other group, reporting PHRs asvirtual PHRs or reporting in accordance with the scheduling condition isconfigured by a higher layer, or only virtual PHRs are reported.

In another aspect of the embodiment, when waveforms used in differentcarries may be different, for example, one carrier uses the OFDMmodulation while another carrier uses the SC-FDMA or OFDM modulation,then when the UE selects one carrier to report the PHR, for example,selects CC1 to report the PHR, the PHR is determined according to thewaveform of CC1. For other carriers, if the PHR is a virtual PHR, thevirtual PHR is calculated according to the predefined waveform. Thepower control parameters corresponding to different waveforms may bedifferent, for example, parameters such as Po and α. Therefore, thevalue of the virtual PHR for different waveforms may also be different.The predefined waveform can be determined by one of the followingmethods: (1) the predefined waveform is a waveform semi-staticallyconfigured for PUSCH transmission, or (2) the predefined waveform is adefault waveform specified by the standard, or (3) the predefinedwaveform is a waveform of a PUSCH transmitted in the last time, and theUE reports, to the base station, the waveform on which the virtual PHRis based, or (4) the predefined waveform is decided by the UE itself,and the UE reports, to the base station, the waveform on which thevirtual PHR is based.

Preferably, when the base station semi-statically instructs the UE tochange the waveform x to waveform y, the accumulation-type closed-looppower control parameter f_(c)(i) for waveform y should be reset asf_(c)(0).

Embodiment 4

Based on the power allocation method provided in Embodiment 1,Embodiment 4 of the present invention provides a user equipment forpower allocation. As shown in FIG. 22, the user equipment comprises apower determination module 1901 and an adjustment module 1902.

Specifically, the power determination module 1901 receives uplinkscheduling information, and determines a corresponding uplink transmitpower on each uplink carrier according to the uplink schedulinginformation, a first reference subframe being a subframe which isdetermined according to the uplink scheduling information to transmit anuplink channel/signal; and, the adjustment module 1902 adjusts,according to an actual maximum uplink transmit power of the firstreference subframe of the user equipment and a predefined firstpriority, the determined uplink transmit power of each uplink carrier,and/or determines whether to transmit an uplink signal.

In the solutions of the present invention, the specific functionimplementation of the modules in the user equipment for power allocationprovided in Embodiment 4 can refer to the specific the steps of thepower allocation method provided in Embodiment 1, and will not berepeated here.

Embodiment 5

Based on the method for reporting headroom provided in Embodiment 2 andEmbodiment 3, Embodiment 5 of the present invention provides a userequipment for reporting power headroom. As shown in FIG. 23, the userequipment comprises a selection module 2001, a PHR value determinationmodule 2002 and a report module 2003.

Specifically, the selection module 2001 selects, from at least oneuplink carrier, one uplink carrier for reporting a Power Headroom Report(PHR) when conditions for reporting the PHR are satisfied, anddetermines an uplink subframe to transmit the PHR, the uplink subframebeing a first reference subframe; the PHR value determination module2002 determines, according to uplink scheduling information received inor before a second reference subframe or according to whether or not acarrier scheduled by two-step scheduling, PHR contents of each uplinkcarrier to be reported on the first reference subframe, and determines acorresponding PHR value according to the PHR contents; and, the reportmodule 2003 generates a PHR of each uplink carrier according to thedetermined PHR value of each uplink carrier, and reports the generatedPHR of each uplink carrier on the selected uplink carrier and in theselected first reference subframe.

In the solutions of the present invention, the specific functionimplementation of the modules in the user equipment for reporting powerheadroom provided in Embodiment 5 can refer to the specific steps of themethod for reporting power headroom provided in Embodiment 2 andEmbodiment 3, and will not be repeated here.

The foregoing descriptions are merely some implementations of thepresent invention. It should be noted that, to a person of ordinaryskill in the art, various improvements and modifications can be madewithout departing from the principle of the present invention, and theseimprovements and modifications shall be regarded as falling into theprotection scope of the present invention.

1. A method for transmitting power headroom information by a terminal in a wireless communication system, the method comprising: generating power headroom information for a serving cell based on whether first uplink scheduling information is received in or earlier than a first subframe on the serving cell, the first uplink scheduling information indicating a transmission in a second subframe; and transmitting, to a base station, the power headroom information in the second subframe.
 2. The method of claim 1, wherein the first uplink scheduling information triggers the transmission in the second subframe on the serving cell if second uplink scheduling information associated with the first uplink scheduling information and indicating a resource allocation for the transmission has been received.
 3. The method of claim 1, wherein the power headroom information for the serving cell is a real power headroom information if the first uplink scheduling information is received, and wherein the power headroom information for the serving cell is a virtual power headroom information if the first uplink scheduling information is not received.
 4. The method of claim 1, wherein the first subframe is prior to the second subframe and a time interval between the first subframe and the second subframe is
 4. 5. A terminal for transmitting power headroom information in a wireless communication system, the terminal comprising: a transceiver configured to transmit and receive signals; and a controlled coupled with the transceiver and configured to generate power headroom information for a serving cell based on whether first uplink scheduling information is received in or earlier than a first subframe on the serving cell, the first uplink scheduling information indicating a transmission in a second subframe, and to transmit, to a base station, the power headroom information in the second subframe.
 6. The terminal of claim 5, wherein the first uplink scheduling information triggers the transmission in the second subframe on the serving cell if second uplink scheduling information associated with the first uplink scheduling information and indicating a resource allocation for the transmission has been received.
 7. The terminal of claim 5, wherein the power headroom information for the serving cell is a real power headroom information if the first uplink scheduling information is received, and wherein the power headroom information for the serving cell is a virtual power headroom information if the first uplink scheduling information is not received.
 8. The terminal of claim 5, wherein the first subframe is prior to the second subframe and a time interval between the first subframe and the second subframe is
 4. 9. A method for receiving power headroom information by a base station in a wireless communication system, the method comprising: transmitting, to a terminal, first uplink scheduling information on a serving cell; transmitting, to the terminal, second uplink scheduling information on the serving cell; and receiving, from the terminal, power headroom information in a first subframe, wherein the power headroom information for the serving cell is generated based on whether the second uplink scheduling information is transmitted in or earlier than a second subframe on the serving cell, the second uplink scheduling information indicating a transmission in the first subframe on the serving cell.
 10. The method of claim 9, wherein the second uplink scheduling information triggers the transmission in the first subframe on the serving cell if the first uplink scheduling information associated with the second uplink scheduling information and indicating a resource allocation for the transmission has been transmitted.
 11. The method of claim 9, wherein the power headroom information for the serving cell is a real power headroom information if the second uplink scheduling information is transmitted, wherein the power headroom information for the serving cell is a virtual power headroom information if the second uplink scheduling information is not transmitted, and wherein the second subframe is prior to the first subframe and a time interval between the second subframe and the first subframe is
 4. 12. A base station for receiving power headroom information in a wireless communication system, the base station comprising: a transceiver configured to transmit and receive signals; and a controller coupled with the transceiver and configured to transmit, to a terminal, first uplink scheduling information on a serving cell, to transmit, to the terminal, second uplink scheduling information on the serving cell, and to receive, from the terminal, power headroom information in a first subframe, wherein the power headroom information for the serving cell is generated based on whether the second uplink scheduling information is transmitted in or earlier than a second subframe on the serving cell, the second uplink scheduling information indicating a transmission in the first subframe on the serving cell.
 13. The base station of claim 12, wherein the second uplink scheduling information triggers the transmission in the first subframe on the serving cell if the first uplink scheduling information associated with the second uplink scheduling information and indicating a resource allocation for the transmission has been transmitted.
 14. The base station of claim 12, wherein the power headroom information for the serving cell is a real power headroom information if the second uplink scheduling information is transmitted, and wherein the power headroom information for the serving cell is a virtual power headroom information if the second uplink scheduling information is not transmitted.
 15. The base station of claim 12, wherein the second subframe is prior to the first subframe and a time interval between the second subframe and the first subframe is
 4. 